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Author SHA1 Message Date
nobody
5a522b9b63 This commit was manufactured by cvs2svn to create tag 'RC_1_30_2'.
[SVN r19443]
2003-08-04 17:55:28 +00:00
Daniel Frey
157111d669 Merged fix for gcc 2.95.2 from HEAD
[SVN r19221]
2003-07-19 20:55:22 +00:00
nobody
469741fa5c This commit was manufactured by cvs2svn to create branch 'RC_1_30_0'.
[SVN r17693]
2003-03-01 19:43:06 +00:00
Jaakko Järvi
02314ab550 typo
[SVN r17652]
2003-02-26 05:11:50 +00:00
Jaakko Järvi
9f032a7301 licences were missing, now added
[SVN r17236]
2003-02-05 15:47:51 +00:00
Jaakko Järvi
da56b773a0 licence fixes ...
[SVN r17235]
2003-02-05 15:41:29 +00:00
Jaakko Järvi
cd605ff48d licence fixe
[SVN r17234]
2003-02-05 15:40:23 +00:00
Jaakko Järvi
641babedf8 added a link
[SVN r17232]
2003-02-05 14:58:37 +00:00
Jaakko Järvi
f9a6b38845 remvoded tabs
[SVN r16828]
2003-01-09 14:15:09 +00:00
Jaakko Järvi
846a406b7a bugfix, added a missing sig template
[SVN r16094]
2002-11-04 16:25:33 +00:00
Jaakko Järvi
29794ee654 added more tests for different arities of member functions
[SVN r16093]
2002-11-04 16:24:38 +00:00
Jaakko Järvi
f74aae1241 bugfixes
[SVN r16025]
2002-10-30 21:10:03 +00:00
Jaakko Järvi
624a204462 a bug fixed
[SVN r15886]
2002-10-10 22:03:49 +00:00
Jaakko Järvi
b635d13d2c a typo fix
[SVN r15656]
2002-10-02 22:43:10 +00:00
Jaakko Järvi
403d82da66 changed a list to a vector (sort requires random access iterator) in one example
[SVN r15575]
2002-09-30 20:28:27 +00:00
Jaakko Järvi
0f29970c8b changing to the new boost::function style
[SVN r15510]
2002-09-25 16:56:06 +00:00
Jaakko Järvi
05b9bd64c4 converting to the new boost::function style
[SVN r15508]
2002-09-25 16:46:42 +00:00
40 changed files with 424 additions and 148 deletions

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@@ -5,7 +5,7 @@
The Boost Lambda Library"><link rel="up" href="index.html" title="
C++ BOOST
The Boost Lambda Library"><link rel="previous" href="ar01s09.html" title="9. Contributors"><link rel="next" href="bi01.html" title="Bibliography"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">A. Rationale for some of the design decisions</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s09.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="bi01.html">Next</a></td></tr></table><hr></div><div class="appendix"><h2 class="title" style="clear: both"><a name="id2808832"></a>A. Rationale for some of the design decisions</h2><div class="section"><div class="titlepage"><div><h3 class="title"><a name="sect:why_weak_arity"></a>1.
The Boost Lambda Library"><link rel="previous" href="ar01s09.html" title="9. Contributors"><link rel="next" href="bi01.html" title="Bibliography"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">A. Rationale for some of the design decisions</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s09.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="bi01.html">Next</a></td></tr></table><hr></div><div class="appendix"><h2 class="title" style="clear: both"><a name="id2808823"></a>A. Rationale for some of the design decisions</h2><div class="section"><div class="titlepage"><div><h3 class="title"><a name="sect:why_weak_arity"></a>1.
Lambda functor arity
</h3></div></div><p>
The highest placeholder index in a lambda expression determines the arity of the resulting function object.

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@@ -8,7 +8,7 @@
The Boost Lambda Library"><link rel="previous" href="index.html" title="
C++ BOOST
The Boost Lambda Library"><link rel="next" href="ar01s03.html" title="3. Introduction"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">2. Getting Started</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="index.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s03.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="sect:getting_started"></a>2. Getting Started</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2790109"></a>2.1. Installing the library</h3></div></div><p>
The Boost Lambda Library"><link rel="next" href="ar01s03.html" title="3. Introduction"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">2. Getting Started</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="index.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s03.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="sect:getting_started"></a>2. Getting Started</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2790118"></a>2.1. Installing the library</h3></div></div><p>
The library consists of include files only, hence there is no
installation procedure. The <tt>boost</tt> include directory
must be on the include path.
@@ -44,7 +44,7 @@ Cast expressions
<span class="emphasis"><i>Tuple</i></span> [<a href="bi01.html#cit:boost::tuple" title="[tuple]">tuple</a>] and the <span class="emphasis"><i>type_traits</i></span> [<a href="bi01.html#cit:boost::type_traits" title="[type_traits]">type_traits</a>] libraries, and on the <tt>boost/ref.hpp</tt> header.
</p><p>
All definitions are placed in the namespace <tt>boost::lambda</tt> and its subnamespaces.
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2741935"></a>2.2. Conventions used in this document</h3></div></div><p>In most code examples, we omit the namespace prefixes for names in the <tt>std</tt> and <tt>boost::lambda</tt> namespaces.
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2741945"></a>2.2. Conventions used in this document</h3></div></div><p>In most code examples, we omit the namespace prefixes for names in the <tt>std</tt> and <tt>boost::lambda</tt> namespaces.
Implicit using declarations
<pre class="programlisting">
using namespace std;

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@@ -5,7 +5,7 @@
The Boost Lambda Library"><link rel="up" href="index.html" title="
C++ BOOST
The Boost Lambda Library"><link rel="previous" href="ar01s02.html" title="2. Getting Started"><link rel="next" href="ar01s04.html" title="4. Using the library"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">3. Introduction</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s02.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s04.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2741982"></a>3. Introduction</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2741989"></a>3.1. Motivation</h3></div></div><p>The Standard Template Library (STL)
The Boost Lambda Library"><link rel="previous" href="ar01s02.html" title="2. Getting Started"><link rel="next" href="ar01s04.html" title="4. Using the library"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">3. Introduction</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s02.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s04.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2741991"></a>3. Introduction</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2741999"></a>3.1. Motivation</h3></div></div><p>The Standard Template Library (STL)
[<a href="bi01.html#cit:stepanov:94" title="[STL94]">STL94</a>], now part of the C++ Standard Library [<a href="bi01.html#cit:c++:98" title="[C++98]">C++98</a>], is a generic container and algorithm library.
Typically STL algorithms operate on container elements via <span class="emphasis"><i>function objects</i></span>. These function objects are passed as arguments to the algorithms.
</p><p>
@@ -105,7 +105,7 @@ as function composition is supported implicitly.
</p></li></ul></div>
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2742784"></a>3.2. Introduction to lambda expressions</h3></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2742792"></a>3.2. Introduction to lambda expressions</h3></div></div><p>
Lambda expression are common in functional programming languages.
Their syntax varies between languages (and between different forms of lambda calculus), but the basic form of a lambda expressions is:

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@@ -20,12 +20,12 @@ There are quite a lot of exceptions and special cases, but discussion of them is
list&lt;int&gt; v(10);
for_each(v.begin(), v.end(), _1 = 1);</pre>
The expression <tt>_1 = 1</tt> creates a lambda functor which assigns the value <tt>1</tt> to every element in <tt>v</tt>.<sup>[<a name="id2739587" href="#ftn.id2739587">1</a>]</sup>
The expression <tt>_1 = 1</tt> creates a lambda functor which assigns the value <tt>1</tt> to every element in <tt>v</tt>.<sup>[<a name="id2739596" href="#ftn.id2739596">1</a>]</sup>
</p><p>
Next, we create a container of pointers and make them point to the elements in the first container <tt>v</tt>:
<pre class="programlisting">
list&lt;int*&gt; vp(10);
vector&lt;int*&gt; vp(10);
transform(v.begin(), v.end(), vp.begin(), &amp;_1);</pre>
The expression <tt>&amp;_1</tt> creates a function object for getting the address of each element in <tt>v</tt>.
@@ -206,7 +206,7 @@ This is to prevent pointer arithmetic making non-const arrays const.
</p></li></ul></div>
</p></li></ul></div>
</p></div><div class="footnotes"><br><hr width="100" align="left"><div class="footnote"><p><sup>[<a name="ftn.id2739587" href="#id2739587">1</a>] </sup>
</p></div><div class="footnotes"><br><hr width="100" align="left"><div class="footnote"><p><sup>[<a name="ftn.id2739596" href="#id2739596">1</a>] </sup>
Strictly taken, the C++ standard defines <tt>for_each</tt> as a <span class="emphasis"><i>non-modifying sequence operation</i></span>, and the function object passed to <tt>for_each</tt> should not modify its argument.
The requirements for the arguments of <tt>for_each</tt> are unnecessary strict, since as long as the iterators are <span class="emphasis"><i>mutable</i></span>, <tt>for_each</tt> accepts a function object that can have side-effects on their argument.
Nevertheless, it is straightforward to provide another function template with the functionality of<tt>std::for_each</tt> but more fine-grained requirements for its arguments.

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@@ -77,7 +77,7 @@ For example, the following is a valid lambda expression:
<pre class="programlisting">cout &lt;&lt; _1, _2[_3] = _1 &amp;&amp; false</pre>
</p><p>
However, there are some restrictions that originate from the C++ operator overloading rules, and some special cases.
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2740636"></a>5.2.1. Operators that cannot be overloaded</h4></div></div><p>
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2740645"></a>5.2.1. Operators that cannot be overloaded</h4></div></div><p>
Some operators cannot be overloaded at all (<tt>::</tt>, <tt>.</tt>, <tt>.*</tt>).
For some operators, the requirements on return types prevent them to be overloaded to create lambda functors.
These operators are <tt>-&gt;.</tt>, <tt>-&gt;</tt>, <tt>new</tt>, <tt>new[]</tt>, <tt>delete</tt>, <tt>delete[]</tt> and <tt>?:</tt> (the conditional operator).
@@ -311,7 +311,7 @@ In general, BLL cannot deduce the return type of an arbitrary function object.
However, there is a method for giving BLL this capability for a certain
function object class.
</p><div class="simplesect"><div class="titlepage"><div><h5 class="title"><a name="id2803238"></a>The sig template</h5></div></div><p>
</p><div class="simplesect"><div class="titlepage"><div><h5 class="title"><a name="id2803246"></a>The sig template</h5></div></div><p>
To make BLL aware of the return type(s) of a function object one needs to
provide a member template struct
<tt>sig&lt;Args&gt;</tt> with a typedef
@@ -533,7 +533,7 @@ By using <tt>var</tt> to make <tt>index</tt> a lambda expression, we get the des
In sum, <tt>var(x)</tt> creates a nullary lambda functor,
which stores a reference to the variable <tt>x</tt>.
When the lambda functor is invoked, a reference to <tt>x</tt> is returned.
</p><div class="simplesect"><div class="titlepage"><div><h4 class="title"><a name="id2804083"></a>Naming delayed constants and variables</h4></div></div><p>
</p><div class="simplesect"><div class="titlepage"><div><h4 class="title"><a name="id2804092"></a>Naming delayed constants and variables</h4></div></div><p>
It is possible to predefine and name a delayed variable or constant outside a lambda expression.
The templates <tt>var_type</tt>, <tt>constant_type</tt>
and <tt>constant_ref_type</tt> serve for this purpose.
@@ -562,7 +562,7 @@ Here is an example of naming a delayed constant:
constant_type&lt;char&gt;::type space(constant(' '));
for_each(a.begin(),a.end(), cout &lt;&lt; space &lt;&lt; _1);
</pre>
</p></div><div class="simplesect"><div class="titlepage"><div><h4 class="title"><a name="id2804207"></a>About assignment and subscript operators</h4></div></div><p>
</p></div><div class="simplesect"><div class="titlepage"><div><h4 class="title"><a name="id2804216"></a>About assignment and subscript operators</h4></div></div><p>
As described in <a href="ar01s05.html#sect:assignment_and_subscript" title="5.2.2. Assignment and subscript operators">Section 5.2.2</a>, assignment and subscripting operators are always defined as member functions.
This means, that for expressions of the form
<tt>x = y</tt> or <tt>x[y]</tt> to be interpreted as lambda expressions, the left-hand operand <tt>x</tt> must be a lambda expression.
@@ -635,13 +635,7 @@ for_each(a, a+5,
The BLL supports an alternative syntax for control expressions, suggested
by Joel de Guzmann.
By overloading the <tt>operator[]</tt> we can
get a closer resemblance with the built-in control structures.
For example, using this syntax the <tt>if_then</tt> example above
can be written as:
<pre class="programlisting">
for_each(a.begin(), a.end(),
if(_1 % 2 == 0)[ cout &lt;&lt; _1 ])
</pre>
get a closer resemblance with the built-in control structures:
<pre class="programlisting">
if_(condition)[then_part]
@@ -651,6 +645,13 @@ do_[body].while_(condition)
for_(init, condition, increment)[body]
</pre>
For example, using this syntax the <tt>if_then</tt> example above
can be written as:
<pre class="programlisting">
for_each(a.begin(), a.end(),
if(_1 % 2 == 0)[ cout &lt;&lt; _1 ])
</pre>
As more experience is gained, we may end up deprecating one or the other
of these syntaces.
@@ -849,7 +850,7 @@ objects related to creating and destroying objects,
showing the expression to create and call the function object,
and the effect of evaluating that expression.
</p><div class="table"><p><a name="table:constructor_destructor_fos"></a><b>Table 1. Construction and destruction related function objects.</b></p><table summary="Construction and destruction related function objects." border="1"><colgroup><col><col></colgroup><thead><tr><th>Function object call</th><th>Wrapped expression</th></tr></thead><tbody><tr><td><tt>constructor&lt;T&gt;()(<i><tt>arg_list</tt></i>)</tt></td><td>T(<i><tt>arg_list</tt></i>)</td></tr><tr><td><tt>destructor()(a)</tt></td><td><tt>a.~A()</tt>, where <tt>a</tt> is of type <tt>A</tt></td></tr><tr><td><tt>destructor()(pa)</tt></td><td><tt>pa.-&gt;A()</tt>, where <tt>pa</tt> is of type <tt>A*</tt></td></tr><tr><td><tt>new_ptr&lt;T&gt;()(<i><tt>arg_list</tt></i>)</tt></td><td><tt>new T(<i><tt>arg_list</tt></i>)</tt></td></tr><tr><td><tt>new_array&lt;T&gt;()(sz)</tt></td><td><tt>new T[sz]</tt></td></tr><tr><td><tt>delete_ptr()(p)</tt></td><td><tt>delete p</tt></td></tr><tr><td><tt>delete_array()(p)</tt></td><td><tt>delete p[]</tt></td></tr></tbody></table></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2805476"></a>5.9. Special lambda expressions</h3></div></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2805483"></a>5.9.1. Preventing argument substitution</h4></div></div><p>
</p><div class="table"><p><a name="table:constructor_destructor_fos"></a><b>Table 1. Construction and destruction related function objects.</b></p><table summary="Construction and destruction related function objects." border="1"><colgroup><col><col></colgroup><thead><tr><th>Function object call</th><th>Wrapped expression</th></tr></thead><tbody><tr><td><tt>constructor&lt;T&gt;()(<i><tt>arg_list</tt></i>)</tt></td><td>T(<i><tt>arg_list</tt></i>)</td></tr><tr><td><tt>destructor()(a)</tt></td><td><tt>a.~A()</tt>, where <tt>a</tt> is of type <tt>A</tt></td></tr><tr><td><tt>destructor()(pa)</tt></td><td><tt>pa.-&gt;A()</tt>, where <tt>pa</tt> is of type <tt>A*</tt></td></tr><tr><td><tt>new_ptr&lt;T&gt;()(<i><tt>arg_list</tt></i>)</tt></td><td><tt>new T(<i><tt>arg_list</tt></i>)</tt></td></tr><tr><td><tt>new_array&lt;T&gt;()(sz)</tt></td><td><tt>new T[sz]</tt></td></tr><tr><td><tt>delete_ptr()(p)</tt></td><td><tt>delete p</tt></td></tr><tr><td><tt>delete_array()(p)</tt></td><td><tt>delete p[]</tt></td></tr></tbody></table></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2805484"></a>5.9. Special lambda expressions</h3></div></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2805492"></a>5.9.1. Preventing argument substitution</h4></div></div><p>
When a lambda functor is called, the default behavior is to substitute
the actual arguments for the placeholders within all subexpressions.
@@ -975,7 +976,7 @@ int nested(const F&amp; f) {
}
</pre>
</p></div><div class="section"><div class="titlepage"><div><h5 class="title"><a name="id2805743"></a>5.9.1.2. Protect</h5></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h5 class="title"><a name="id2805751"></a>5.9.1.2. Protect</h5></div></div><p>
The <tt>protect</tt> function is related to unlambda.
It is also used to prevent the argument substitution taking place,
@@ -1080,7 +1081,7 @@ since calls to sub lambda functors are made inside the BLL,
and are not affected by the non-const rvalue problem.
</p></li></ol></div>
</p></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2806049"></a>5.10. Casts, sizeof and typeid</h3></div></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="sect:cast_expressions"></a>5.10.1.
</p></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2806057"></a>5.10. Casts, sizeof and typeid</h3></div></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="sect:cast_expressions"></a>5.10.1.
Cast expressions
</h4></div></div><p>
The BLL defines its counterparts for the four cast expressions
@@ -1109,7 +1110,7 @@ int count = 0;
for_each(a.begin(), a.end(),
if_then(ll_dynamic_cast&lt;derived*&gt;(_1), ++var(count)));
</pre>
</p></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2806151"></a>5.10.2. Sizeof and typeid</h4></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2806159"></a>5.10.2. Sizeof and typeid</h4></div></div><p>
The BLL counterparts for these expressions are named
<tt>ll_sizeof</tt> and <tt>ll_typeid</tt>.

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@@ -5,7 +5,7 @@
The Boost Lambda Library"><link rel="up" href="index.html" title="
C++ BOOST
The Boost Lambda Library"><link rel="previous" href="ar01s06.html" title="6. Extending return type deduction system"><link rel="next" href="ar01s08.html" title="8. Relation to other Boost libraries"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">7. Practical considerations</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s06.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s08.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2807558"></a>7. Practical considerations</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2807564"></a>7.1. Performance</h3></div></div><p>In theory, all overhead of using STL algorithms and lambda functors
The Boost Lambda Library"><link rel="previous" href="ar01s06.html" title="6. Extending return type deduction system"><link rel="next" href="ar01s08.html" title="8. Relation to other Boost libraries"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">7. Practical considerations</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s06.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s08.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2807566"></a>7. Practical considerations</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2807572"></a>7.1. Performance</h3></div></div><p>In theory, all overhead of using STL algorithms and lambda functors
compared to hand written loops can be optimized away, just as the overhead
from standard STL function objects and binders can.
@@ -75,7 +75,7 @@ Note however, that evaluating a lambda functor consist of a sequence of calls to
If the compiler fails to actually expand these functions inline,
the performance can suffer.
The running time can more than double if this happens.
Although the above tests do not include such an expression, we have experiensed
Although the above tests do not include such an expression, we have experienced
this for some seemingly simple expressions.
@@ -97,7 +97,7 @@ The running times are expressed in arbitrary units." border="1"><colgroup><col><
</p><p>Some additional performance testing with an earlier version of the
library is described
[<a href="bi01.html#cit:jarvi:00" title="[Jär00]">Jär00</a>].
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2808057"></a>7.2. About compiling</h3></div></div><p>The BLL uses templates rather heavily, performing numerous recursive instantiations of the same templates.
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2808065"></a>7.2. About compiling</h3></div></div><p>The BLL uses templates rather heavily, performing numerous recursive instantiations of the same templates.
This has (at least) three implications:
<div class="itemizedlist"><ul type="disc"><li><p>
While it is possible to write incredibly complex lambda expressions, it probably isn't a good idea.
@@ -111,7 +111,7 @@ This can make the error messages very long and difficult to interpret, particula
The C++ Standard suggests a template nesting level of 17 to help detect infinite recursion.
Complex lambda templates can easily exceed this limit.
Most compilers allow a greater number of nested templates, but commonly require the limit explicitly increased with a command line argument.
</p></li></ul></div></p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2808118"></a>7.3. Portability</h3></div></div><p>
</p></li></ul></div></p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2808126"></a>7.3. Portability</h3></div></div><p>
The BLL works with the following compilers, that is, the compilers are capable of compiling the test cases that are included with the BLL:
<div class="itemizedlist"><ul type="disc"><li>GCC 3.0.4
@@ -120,7 +120,7 @@ The BLL works with the following compilers, that is, the compilers are capable o
)
</li></ul></div>
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2808157"></a>7.3.1. Test coverage</h4></div></div><p>The following list describes the test files included and the features that each file covers:
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2808166"></a>7.3.1. Test coverage</h4></div></div><p>The following list describes the test files included and the features that each file covers:
<div class="itemizedlist"><ul type="disc"><li><p>
<tt>bind_tests_simple.cpp</tt> : Bind expressions of different arities and types of target functions: function pointers, function objects and member functions.

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@@ -5,7 +5,7 @@
The Boost Lambda Library"><link rel="up" href="index.html" title="
C++ BOOST
The Boost Lambda Library"><link rel="previous" href="ar01s07.html" title="7. Practical considerations"><link rel="next" href="ar01s09.html" title="9. Contributors"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">8. Relation to other Boost libraries</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s07.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s09.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2808502"></a>8. Relation to other Boost libraries</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2808510"></a>8.1. Boost Function</h3></div></div><p>Sometimes it is convenient to store lambda functors in variables.
The Boost Lambda Library"><link rel="previous" href="ar01s07.html" title="7. Practical considerations"><link rel="next" href="ar01s09.html" title="9. Contributors"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">8. Relation to other Boost libraries</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s07.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s09.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2808510"></a>8. Relation to other Boost libraries</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2808518"></a>8.1. Boost Function</h3></div></div><p>Sometimes it is convenient to store lambda functors in variables.
However, the types of even the simplest lambda functors are long and unwieldy, and it is in general unfeasible to declare variables with lambda functor types.
<span class="emphasis"><i>The Boost Function library</i></span> [<a href="bi01.html#cit:boost::function" title="[function]">function</a>] defines wrappers for arbitrary function objects, for example
lambda functors; and these wrappers have types that are easy to type out.
@@ -13,14 +13,14 @@ lambda functors; and these wrappers have types that are easy to type out.
For example:
<pre class="programlisting">
boost::function&lt;int, int, int&gt; f = _1 + _2;
boost::function&lt;int&amp;, int&amp;&gt; g = unlambda(_1 += 10);
boost::function&lt;int(int, int)&gt; f = _1 + _2;
boost::function&lt;int&amp;(int&amp;)&gt; g = (_1 += 10);
int i = 1, j = 2;
f(i); // returns 3
g(i); // sets i to = 11;
</pre>
The return and parameter types of the wrapped function object must be written explicilty as template arguments to the wrapper template <tt>boost::function</tt>; even when lambda functors, which otherwise have generic parameters, are wrapped.
The return and parameter types of the wrapped function object must be written explicilty as the template argument to the wrapper template <tt>boost::function</tt>; even when lambda functors, which otherwise have generic parameters, are wrapped.
Wrapping a function object with <tt>boost::function</tt> introduces a performance cost comparable to virtual function dispatch, though virtual functions are not actually used.
Note that storing lambda functors inside <tt>boost::function</tt>
@@ -38,13 +38,13 @@ For example:
<pre class="programlisting">
int* sum = new int();
*sum = 0;
boost::function&lt;int&amp;, int&gt; counter = *sum += _1;
boost::function&lt;int&amp;(int)&gt; counter = *sum += _1;
counter(5); // ok, *sum = 5;
delete sum;
counter(3); // error, *sum does not exist anymore
</pre>
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2808614"></a>8.2. Boost Bind</h3></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2808622"></a>8.2. Boost Bind</h3></div></div><p>
<span class="emphasis"><i>The Boost Bind</i></span> [<a href="bi01.html#cit:boost::bind" title="[bind]">bind</a>] library has partially overlapping functionality with the BLL.
Basically, the Boost Bind library (BB in the sequel) implements the bind expression part of BLL.
There are, however, some semantical differerences.
@@ -63,7 +63,7 @@ a larger set of compilers.
</p><p>
The following two sections describe what are the semantic differences
between the bind expressions in BB and BLL.
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2808678"></a>8.2.1. First argument of bind expression</h4></div></div>
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2808686"></a>8.2.1. First argument of bind expression</h4></div></div>
In BB the first argument of the bind expression, the target function,
is treated differently from the other arguments,

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@@ -5,7 +5,7 @@
The Boost Lambda Library"><link rel="up" href="index.html" title="
C++ BOOST
The Boost Lambda Library"><link rel="previous" href="ar01s08.html" title="8. Relation to other Boost libraries"><link rel="next" href="apa.html" title="A. Rationale for some of the design decisions"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">9. Contributors</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s08.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="apa.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2808810"></a>9. Contributors</h2></div></div>
The Boost Lambda Library"><link rel="previous" href="ar01s08.html" title="8. Relation to other Boost libraries"><link rel="next" href="apa.html" title="A. Rationale for some of the design decisions"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">9. Contributors</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s08.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="apa.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2808801"></a>9. Contributors</h2></div></div>
The main body of the library was written by Jaakko Järvi and Gary Powell.
We've got outside help, suggestions and ideas from Jeremy Siek, Peter Higley, Peter Dimov, Valentin Bonnard, William Kempf.

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@@ -5,7 +5,7 @@
The Boost Lambda Library"><link rel="up" href="index.html" title="
C++ BOOST
The Boost Lambda Library"><link rel="previous" href="apa.html" title="A. Rationale for some of the design decisions"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Bibliography</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="apa.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> </td></tr></table><hr></div><div id="id2808984" class="bibliography"><div class="titlepage"><div><h2 class="title"><a name="id2808984"></a>Bibliography</h2></div></div><div class="biblioentry"><a name="cit:stepanov:94"></a><p>[STL94] <span class="authorgroup">A. A. Stepanov and M. Lee. </span><span class="title"><I>The Standard Template Library</I>. </span><span class="orgname">Hewlett-Packard Laboratories. </span><span class="pubdate">1994. </span><span class="bibliomisc">
The Boost Lambda Library"><link rel="previous" href="apa.html" title="A. Rationale for some of the design decisions"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Bibliography</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="apa.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> </td></tr></table><hr></div><div id="id2808975" class="bibliography"><div class="titlepage"><div><h2 class="title"><a name="id2808975"></a>Bibliography</h2></div></div><div class="biblioentry"><a name="cit:stepanov:94"></a><p>[STL94] <span class="authorgroup">A. A. Stepanov and M. Lee. </span><span class="title"><I>The Standard Template Library</I>. </span><span class="orgname">Hewlett-Packard Laboratories. </span><span class="pubdate">1994. </span><span class="bibliomisc">
<a href="http://www.hpl.hp.com/techreports" target="_top">www.hpl.hp.com/techreports</a>
. </span></p></div><div class="biblioentry"><a name="cit:sgi:02"></a><p>[SGI02] <span class="title"><I>The SGI Standard Template Library</I>. </span><span class="pubdate">2002. </span><span class="bibliomisc"><a href="http://www.sgi.com/tech/stl/" target="_top">www.sgi.com/tech/stl/</a>. </span></p></div><div class="biblioentry"><a name="cit:c++:98"></a><p>[C++98] <span class="title"><I>International Standard, Programming Languages &#8211; C++</I>. </span><span class="subtitle">ISO/IEC:14882. </span><span class="pubdate">1998. </span></p></div><div class="biblioentry"><a name="cit:jarvi:99"></a><p>[Jär99] <span class="articleinfo">
<span class="author">Jaakko Järvi. </span>

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@@ -2,6 +2,6 @@
generated
- lambda_doc_chunks.xsl loads the stylesheets that generate a separate
html-file for each section
- lambda_doc.html loads stylesheets that generate one big html-file
- lambda_doc.xsl loads stylesheets that generate one big html-file
(you need to edit the paths in these files to make them work)

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@@ -44,6 +44,7 @@
<!-- -->
<ulink url="lambda_docs_as_one_file.html">Documentation as a one big HTML-file</ulink>
<section id="introduction">
@@ -444,7 +445,7 @@ Nevertheless, it is straightforward to provide another function template with th
Next, we create a container of pointers and make them point to the elements in the first container <literal>v</literal>:
<programlisting>
<![CDATA[list<int*> vp(10);
<![CDATA[vector<int*> vp(10);
transform(v.begin(), v.end(), vp.begin(), &_1);]]></programlisting>
The expression <literal><![CDATA[&_1]]></literal> creates a function object for getting the address of each element in <literal>v</literal>.
@@ -1578,13 +1579,7 @@ for_each(a, a+5,
The BLL supports an alternative syntax for control expressions, suggested
by Joel de Guzmann.
By overloading the <literal>operator[]</literal> we can
get a closer resemblance with the built-in control structures.
For example, using this syntax the <literal>if_then</literal> example above
can be written as:
<programlisting>
<![CDATA[for_each(a.begin(), a.end(),
if(_1 % 2 == 0)[ cout << _1 ])]]>
</programlisting>
get a closer resemblance with the built-in control structures:
<programlisting>
<![CDATA[if_(condition)[then_part]
@@ -1594,6 +1589,13 @@ do_[body].while_(condition)
for_(init, condition, increment)[body]]]>
</programlisting>
For example, using this syntax the <literal>if_then</literal> example above
can be written as:
<programlisting>
<![CDATA[for_each(a.begin(), a.end(),
if(_1 % 2 == 0)[ cout << _1 ])]]>
</programlisting>
As more experience is gained, we may end up deprecating one or the other
of these syntaces.
@@ -2719,7 +2721,7 @@ Note however, that evaluating a lambda functor consist of a sequence of calls to
If the compiler fails to actually expand these functions inline,
the performance can suffer.
The running time can more than double if this happens.
Although the above tests do not include such an expression, we have experiensed
Although the above tests do not include such an expression, we have experienced
this for some seemingly simple expressions.
@@ -3029,14 +3031,14 @@ lambda functors; and these wrappers have types that are easy to type out.
For example:
<programlisting>
<![CDATA[boost::function<int, int, int> f = _1 + _2;
boost::function<int&, int&> g = unlambda(_1 += 10);
<![CDATA[boost::function<int(int, int)> f = _1 + _2;
boost::function<int&(int&)> g = (_1 += 10);
int i = 1, j = 2;
f(i); // returns 3
g(i); // sets i to = 11;]]>
</programlisting>
The return and parameter types of the wrapped function object must be written explicilty as template arguments to the wrapper template <literal>boost::function</literal>; even when lambda functors, which otherwise have generic parameters, are wrapped.
The return and parameter types of the wrapped function object must be written explicilty as the template argument to the wrapper template <literal>boost::function</literal>; even when lambda functors, which otherwise have generic parameters, are wrapped.
Wrapping a function object with <literal>boost::function</literal> introduces a performance cost comparable to virtual function dispatch, though virtual functions are not actually used.
Note that storing lambda functors inside <literal>boost::function</literal>
@@ -3054,7 +3056,7 @@ For example:
<programlisting>
<![CDATA[int* sum = new int();
*sum = 0;
boost::function<int&, int> counter = *sum += _1;
boost::function<int&(int)> counter = *sum += _1;
counter(5); // ok, *sum = 5;
delete sum;
counter(3); // error, *sum does not exist anymore]]>

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@@ -15,9 +15,9 @@
The Boost Lambda Library is free software; Permission to copy,
use, modify and distribute this software and its documentation is granted, provided this copyright
notice appears in all copies.
</p></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt>1. <a href="index.html#introduction">In a nutshell</a></dt><dt>2. <a href="ar01s02.html">Getting Started</a></dt><dd><dl><dt>2.1. <a href="ar01s02.html#id2790109">Installing the library</a></dt><dt>2.2. <a href="ar01s02.html#id2741935">Conventions used in this document</a></dt></dl></dd><dt>3. <a href="ar01s03.html">Introduction</a></dt><dd><dl><dt>3.1. <a href="ar01s03.html#id2741989">Motivation</a></dt><dt>3.2. <a href="ar01s03.html#id2742784">Introduction to lambda expressions</a></dt></dl></dd><dt>4. <a href="ar01s04.html">Using the library</a></dt><dd><dl><dt>4.1. <a href="ar01s04.html#sect:introductory_examples">Introductory Examples</a></dt><dt>4.2. <a href="ar01s04.html#sect:parameter_and_return_types">Parameter and return types of lambda functors</a></dt><dt>4.3. <a href="ar01s04.html#sect:actual_arguments_to_lambda_functors">About actual arguments to lambda functors</a></dt><dt>4.4. <a href="ar01s04.html#sect:storing_bound_arguments">Storing bound arguments in lambda functions</a></dt></dl></dd><dt>5. <a href="ar01s05.html">Lambda expressions in details</a></dt><dd><dl><dt>5.1. <a href="ar01s05.html#sect:placeholders">Placeholders</a></dt><dt>5.2. <a href="ar01s05.html#sect:operator_expressions">Operator expressions</a></dt><dt>5.3. <a href="ar01s05.html#sect:bind_expressions">Bind expressions</a></dt><dt>5.4. <a href="ar01s05.html#sect:overriding_deduced_return_type">Overriding the deduced return type</a></dt><dt>5.5. <a href="ar01s05.html#sect:delaying_constants_and_variables">Delaying constants and variables</a></dt><dt>5.6. <a href="ar01s05.html#sect:lambda_expressions_for_control_structures">Lambda expressions for control structures</a></dt><dt>5.7. <a href="ar01s05.html#sect:exceptions">Exceptions</a></dt><dt>5.8. <a href="ar01s05.html#sect:construction_and_destruction">Construction and destruction</a></dt><dt>5.9. <a href="ar01s05.html#id2805476">Special lambda expressions</a></dt><dt>5.10. <a href="ar01s05.html#id2806049">Casts, sizeof and typeid</a></dt><dt>5.11. <a href="ar01s05.html#sect:nested_stl_algorithms">Nesting STL algorithm invocations</a></dt></dl></dd><dt>6. <a href="ar01s06.html">Extending return type deduction system</a></dt><dt>7. <a href="ar01s07.html">Practical considerations</a></dt><dd><dl><dt>7.1. <a href="ar01s07.html#id2807564">Performance</a></dt><dt>7.2. <a href="ar01s07.html#id2808057">About compiling</a></dt><dt>7.3. <a href="ar01s07.html#id2808118">Portability</a></dt></dl></dd><dt>8. <a href="ar01s08.html">Relation to other Boost libraries</a></dt><dd><dl><dt>8.1. <a href="ar01s08.html#id2808510">Boost Function</a></dt><dt>8.2. <a href="ar01s08.html#id2808614">Boost Bind</a></dt></dl></dd><dt>9. <a href="ar01s09.html">Contributors</a></dt><dt>A. <a href="apa.html">Rationale for some of the design decisions</a></dt><dd><dl><dt>1. <a href="apa.html#sect:why_weak_arity">
</p></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt>1. <a href="index.html#introduction">In a nutshell</a></dt><dt>2. <a href="ar01s02.html">Getting Started</a></dt><dd><dl><dt>2.1. <a href="ar01s02.html#id2790118">Installing the library</a></dt><dt>2.2. <a href="ar01s02.html#id2741945">Conventions used in this document</a></dt></dl></dd><dt>3. <a href="ar01s03.html">Introduction</a></dt><dd><dl><dt>3.1. <a href="ar01s03.html#id2741999">Motivation</a></dt><dt>3.2. <a href="ar01s03.html#id2742792">Introduction to lambda expressions</a></dt></dl></dd><dt>4. <a href="ar01s04.html">Using the library</a></dt><dd><dl><dt>4.1. <a href="ar01s04.html#sect:introductory_examples">Introductory Examples</a></dt><dt>4.2. <a href="ar01s04.html#sect:parameter_and_return_types">Parameter and return types of lambda functors</a></dt><dt>4.3. <a href="ar01s04.html#sect:actual_arguments_to_lambda_functors">About actual arguments to lambda functors</a></dt><dt>4.4. <a href="ar01s04.html#sect:storing_bound_arguments">Storing bound arguments in lambda functions</a></dt></dl></dd><dt>5. <a href="ar01s05.html">Lambda expressions in details</a></dt><dd><dl><dt>5.1. <a href="ar01s05.html#sect:placeholders">Placeholders</a></dt><dt>5.2. <a href="ar01s05.html#sect:operator_expressions">Operator expressions</a></dt><dt>5.3. <a href="ar01s05.html#sect:bind_expressions">Bind expressions</a></dt><dt>5.4. <a href="ar01s05.html#sect:overriding_deduced_return_type">Overriding the deduced return type</a></dt><dt>5.5. <a href="ar01s05.html#sect:delaying_constants_and_variables">Delaying constants and variables</a></dt><dt>5.6. <a href="ar01s05.html#sect:lambda_expressions_for_control_structures">Lambda expressions for control structures</a></dt><dt>5.7. <a href="ar01s05.html#sect:exceptions">Exceptions</a></dt><dt>5.8. <a href="ar01s05.html#sect:construction_and_destruction">Construction and destruction</a></dt><dt>5.9. <a href="ar01s05.html#id2805484">Special lambda expressions</a></dt><dt>5.10. <a href="ar01s05.html#id2806057">Casts, sizeof and typeid</a></dt><dt>5.11. <a href="ar01s05.html#sect:nested_stl_algorithms">Nesting STL algorithm invocations</a></dt></dl></dd><dt>6. <a href="ar01s06.html">Extending return type deduction system</a></dt><dt>7. <a href="ar01s07.html">Practical considerations</a></dt><dd><dl><dt>7.1. <a href="ar01s07.html#id2807572">Performance</a></dt><dt>7.2. <a href="ar01s07.html#id2808065">About compiling</a></dt><dt>7.3. <a href="ar01s07.html#id2808126">Portability</a></dt></dl></dd><dt>8. <a href="ar01s08.html">Relation to other Boost libraries</a></dt><dd><dl><dt>8.1. <a href="ar01s08.html#id2808518">Boost Function</a></dt><dt>8.2. <a href="ar01s08.html#id2808622">Boost Bind</a></dt></dl></dd><dt>9. <a href="ar01s09.html">Contributors</a></dt><dt>A. <a href="apa.html">Rationale for some of the design decisions</a></dt><dd><dl><dt>1. <a href="apa.html#sect:why_weak_arity">
Lambda functor arity
</a></dt></dl></dd><dt><a href="bi01.html">Bibliography</a></dt></dl></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="introduction"></a>1. In a nutshell</h2></div></div><p>
</a></dt></dl></dd><dt><a href="bi01.html">Bibliography</a></dt></dl></div><a href="lambda_docs_as_one_file.html" target="_top">Documentation as a one big HTML-file</a><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="introduction"></a>1. In a nutshell</h2></div></div><p>
The Boost Lambda Library (BLL in the sequel) is a C++ template
library, which implements form of <span class="emphasis"><i>lambda abstractions</i></span> for C++.

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@@ -1,16 +1,16 @@
<html><head><meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"><title>
C++ BOOST
The Boost Lambda Library</title><meta name="generator" content="DocBook XSL Stylesheets V1.48"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="article"><div class="titlepage"><div><h1 class="title"><a name="id2732401"></a>
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The Boost Lambda Library</h1></div><div><p class="copyright">Copyright © 1999-2002 Jaakko Järvi, Gary Powell</p></div><div><div class="legalnotice"><p>
The Boost Lambda Library is free software; Permission to copy,
use, modify and distribute this software and its documentation is granted, provided this copyright
notice appears in all copies.
</p></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt>1. <a href="#introduction">In a nutshell</a></dt><dt>2. <a href="#sect:getting_started">Getting Started</a></dt><dd><dl><dt>2.1. <a href="#id2779428">Installing the library</a></dt><dt>2.2. <a href="#id2733541">Conventions used in this document</a></dt></dl></dd><dt>3. <a href="#id2733588">Introduction</a></dt><dd><dl><dt>3.1. <a href="#id2733595">Motivation</a></dt><dt>3.2. <a href="#id2733932">Introduction to lambda expressions</a></dt></dl></dd><dt>4. <a href="#sect:using_library">Using the library</a></dt><dd><dl><dt>4.1. <a href="#sect:introductory_examples">Introductory Examples</a></dt><dt>4.2. <a href="#sect:parameter_and_return_types">Parameter and return types of lambda functors</a></dt><dt>4.3. <a href="#sect:actual_arguments_to_lambda_functors">About actual arguments to lambda functors</a></dt><dt>4.4. <a href="#sect:storing_bound_arguments">Storing bound arguments in lambda functions</a></dt></dl></dd><dt>5. <a href="#sect:lambda_expressions_in_details">Lambda expressions in details</a></dt><dd><dl><dt>5.1. <a href="#sect:placeholders">Placeholders</a></dt><dt>5.2. <a href="#sect:operator_expressions">Operator expressions</a></dt><dt>5.3. <a href="#sect:bind_expressions">Bind expressions</a></dt><dt>5.4. <a href="#sect:overriding_deduced_return_type">Overriding the deduced return type</a></dt><dt>5.5. <a href="#sect:delaying_constants_and_variables">Delaying constants and variables</a></dt><dt>5.6. <a href="#sect:lambda_expressions_for_control_structures">Lambda expressions for control structures</a></dt><dt>5.7. <a href="#sect:exceptions">Exceptions</a></dt><dt>5.8. <a href="#sect:construction_and_destruction">Construction and destruction</a></dt><dt>5.9. <a href="#id2794800">Special lambda expressions</a></dt><dt>5.10. <a href="#id2795373">Casts, sizeof and typeid</a></dt><dt>5.11. <a href="#sect:nested_stl_algorithms">Nesting STL algorithm invocations</a></dt></dl></dd><dt>6. <a href="#sect:extending_return_type_system">Extending return type deduction system</a></dt><dt>7. <a href="#id2796882">Practical considerations</a></dt><dd><dl><dt>7.1. <a href="#id2796888">Performance</a></dt><dt>7.2. <a href="#id2797381">About compiling</a></dt><dt>7.3. <a href="#id2797442">Portability</a></dt></dl></dd><dt>8. <a href="#id2797826">Relation to other Boost libraries</a></dt><dd><dl><dt>8.1. <a href="#id2797834">Boost Function</a></dt><dt>8.2. <a href="#id2797938">Boost Bind</a></dt></dl></dd><dt>9. <a href="#id2798134">Contributors</a></dt><dt>A. <a href="#id2798156">Rationale for some of the design decisions</a></dt><dd><dl><dt>1. <a href="#sect:why_weak_arity">
</p></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt>1. <a href="#introduction">In a nutshell</a></dt><dt>2. <a href="#sect:getting_started">Getting Started</a></dt><dd><dl><dt>2.1. <a href="#id2779436">Installing the library</a></dt><dt>2.2. <a href="#id2733553">Conventions used in this document</a></dt></dl></dd><dt>3. <a href="#id2733600">Introduction</a></dt><dd><dl><dt>3.1. <a href="#id2733607">Motivation</a></dt><dt>3.2. <a href="#id2733935">Introduction to lambda expressions</a></dt></dl></dd><dt>4. <a href="#sect:using_library">Using the library</a></dt><dd><dl><dt>4.1. <a href="#sect:introductory_examples">Introductory Examples</a></dt><dt>4.2. <a href="#sect:parameter_and_return_types">Parameter and return types of lambda functors</a></dt><dt>4.3. <a href="#sect:actual_arguments_to_lambda_functors">About actual arguments to lambda functors</a></dt><dt>4.4. <a href="#sect:storing_bound_arguments">Storing bound arguments in lambda functions</a></dt></dl></dd><dt>5. <a href="#sect:lambda_expressions_in_details">Lambda expressions in details</a></dt><dd><dl><dt>5.1. <a href="#sect:placeholders">Placeholders</a></dt><dt>5.2. <a href="#sect:operator_expressions">Operator expressions</a></dt><dt>5.3. <a href="#sect:bind_expressions">Bind expressions</a></dt><dt>5.4. <a href="#sect:overriding_deduced_return_type">Overriding the deduced return type</a></dt><dt>5.5. <a href="#sect:delaying_constants_and_variables">Delaying constants and variables</a></dt><dt>5.6. <a href="#sect:lambda_expressions_for_control_structures">Lambda expressions for control structures</a></dt><dt>5.7. <a href="#sect:exceptions">Exceptions</a></dt><dt>5.8. <a href="#sect:construction_and_destruction">Construction and destruction</a></dt><dt>5.9. <a href="#id2794809">Special lambda expressions</a></dt><dt>5.10. <a href="#id2795382">Casts, sizeof and typeid</a></dt><dt>5.11. <a href="#sect:nested_stl_algorithms">Nesting STL algorithm invocations</a></dt></dl></dd><dt>6. <a href="#sect:extending_return_type_system">Extending return type deduction system</a></dt><dt>7. <a href="#id2796890">Practical considerations</a></dt><dd><dl><dt>7.1. <a href="#id2796897">Performance</a></dt><dt>7.2. <a href="#id2797390">About compiling</a></dt><dt>7.3. <a href="#id2797451">Portability</a></dt></dl></dd><dt>8. <a href="#id2797835">Relation to other Boost libraries</a></dt><dd><dl><dt>8.1. <a href="#id2797842">Boost Function</a></dt><dt>8.2. <a href="#id2797946">Boost Bind</a></dt></dl></dd><dt>9. <a href="#id2798126">Contributors</a></dt><dt>A. <a href="#id2798147">Rationale for some of the design decisions</a></dt><dd><dl><dt>1. <a href="#sect:why_weak_arity">
Lambda functor arity
</a></dt></dl></dd><dt><a href="#id2798308">Bibliography</a></dt></dl></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="introduction"></a>1. In a nutshell</h2></div></div><p>
</a></dt></dl></dd><dt><a href="#id2798300">Bibliography</a></dt></dl></div><a href="lambda_docs_as_one_file.html" target="_top">Documentation as a one big HTML-file</a><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="introduction"></a>1. In a nutshell</h2></div></div><p>
The Boost Lambda Library (BLL in the sequel) is a C++ template
library, which implements form of <span class="emphasis"><i>lambda abstractions</i></span> for C++.
@@ -29,7 +29,7 @@ In explaining what the library is about, a line of code says more than a thousan
called with an element of <tt>a</tt> as the actual argument.
This actual argument is substituted for the placeholder, and the &#8216;body&#8217; of the function is evaluated.
</p><p>The essence of BLL is letting you define small unnamed function objects, such as the one above, directly on the call site of an STL algorithm.
</p></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="sect:getting_started"></a>2. Getting Started</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2779428"></a>2.1. Installing the library</h3></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="sect:getting_started"></a>2. Getting Started</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2779436"></a>2.1. Installing the library</h3></div></div><p>
The library consists of include files only, hence there is no
installation procedure. The <tt>boost</tt> include directory
must be on the include path.
@@ -65,14 +65,14 @@ Cast expressions
<span class="emphasis"><i>Tuple</i></span> [<a href="#cit:boost::tuple" title="[tuple]">tuple</a>] and the <span class="emphasis"><i>type_traits</i></span> [<a href="#cit:boost::type_traits" title="[type_traits]">type_traits</a>] libraries, and on the <tt>boost/ref.hpp</tt> header.
</p><p>
All definitions are placed in the namespace <tt>boost::lambda</tt> and its subnamespaces.
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2733541"></a>2.2. Conventions used in this document</h3></div></div><p>In most code examples, we omit the namespace prefixes for names in the <tt>std</tt> and <tt>boost::lambda</tt> namespaces.
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2733553"></a>2.2. Conventions used in this document</h3></div></div><p>In most code examples, we omit the namespace prefixes for names in the <tt>std</tt> and <tt>boost::lambda</tt> namespaces.
Implicit using declarations
<pre class="programlisting">
using namespace std;
using namespace boost::lambda;
</pre>
are assumed to be in effect.
</p></div></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2733588"></a>3. Introduction</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2733595"></a>3.1. Motivation</h3></div></div><p>The Standard Template Library (STL)
</p></div></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2733600"></a>3. Introduction</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2733607"></a>3.1. Motivation</h3></div></div><p>The Standard Template Library (STL)
[<a href="#cit:stepanov:94" title="[STL94]">STL94</a>], now part of the C++ Standard Library [<a href="#cit:c++:98" title="[C++98]">C++98</a>], is a generic container and algorithm library.
Typically STL algorithms operate on container elements via <span class="emphasis"><i>function objects</i></span>. These function objects are passed as arguments to the algorithms.
</p><p>
@@ -172,7 +172,7 @@ as function composition is supported implicitly.
</p></li></ul></div>
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2733932"></a>3.2. Introduction to lambda expressions</h3></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2733935"></a>3.2. Introduction to lambda expressions</h3></div></div><p>
Lambda expression are common in functional programming languages.
Their syntax varies between languages (and between different forms of lambda calculus), but the basic form of a lambda expressions is:
@@ -254,12 +254,12 @@ There are quite a lot of exceptions and special cases, but discussion of them is
list&lt;int&gt; v(10);
for_each(v.begin(), v.end(), _1 = 1);</pre>
The expression <tt>_1 = 1</tt> creates a lambda functor which assigns the value <tt>1</tt> to every element in <tt>v</tt>.<sup>[<a name="id2729061" href="#ftn.id2729061">1</a>]</sup>
The expression <tt>_1 = 1</tt> creates a lambda functor which assigns the value <tt>1</tt> to every element in <tt>v</tt>.<sup>[<a name="id2729070" href="#ftn.id2729070">1</a>]</sup>
</p><p>
Next, we create a container of pointers and make them point to the elements in the first container <tt>v</tt>:
<pre class="programlisting">
list&lt;int*&gt; vp(10);
vector&lt;int*&gt; vp(10);
transform(v.begin(), v.end(), vp.begin(), &amp;_1);</pre>
The expression <tt>&amp;_1</tt> creates a function object for getting the address of each element in <tt>v</tt>.
@@ -512,7 +512,7 @@ For example, the following is a valid lambda expression:
<pre class="programlisting">cout &lt;&lt; _1, _2[_3] = _1 &amp;&amp; false</pre>
</p><p>
However, there are some restrictions that originate from the C++ operator overloading rules, and some special cases.
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2730141"></a>5.2.1. Operators that cannot be overloaded</h4></div></div><p>
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2730150"></a>5.2.1. Operators that cannot be overloaded</h4></div></div><p>
Some operators cannot be overloaded at all (<tt>::</tt>, <tt>.</tt>, <tt>.*</tt>).
For some operators, the requirements on return types prevent them to be overloaded to create lambda functors.
These operators are <tt>-&gt;.</tt>, <tt>-&gt;</tt>, <tt>new</tt>, <tt>new[]</tt>, <tt>delete</tt>, <tt>delete[]</tt> and <tt>?:</tt> (the conditional operator).
@@ -746,7 +746,7 @@ In general, BLL cannot deduce the return type of an arbitrary function object.
However, there is a method for giving BLL this capability for a certain
function object class.
</p><div class="simplesect"><div class="titlepage"><div><h5 class="title"><a name="id2792562"></a>The sig template</h5></div></div><p>
</p><div class="simplesect"><div class="titlepage"><div><h5 class="title"><a name="id2792571"></a>The sig template</h5></div></div><p>
To make BLL aware of the return type(s) of a function object one needs to
provide a member template struct
<tt>sig&lt;Args&gt;</tt> with a typedef
@@ -968,7 +968,7 @@ By using <tt>var</tt> to make <tt>index</tt> a lambda expression, we get the des
In sum, <tt>var(x)</tt> creates a nullary lambda functor,
which stores a reference to the variable <tt>x</tt>.
When the lambda functor is invoked, a reference to <tt>x</tt> is returned.
</p><div class="simplesect"><div class="titlepage"><div><h4 class="title"><a name="id2793408"></a>Naming delayed constants and variables</h4></div></div><p>
</p><div class="simplesect"><div class="titlepage"><div><h4 class="title"><a name="id2793417"></a>Naming delayed constants and variables</h4></div></div><p>
It is possible to predefine and name a delayed variable or constant outside a lambda expression.
The templates <tt>var_type</tt>, <tt>constant_type</tt>
and <tt>constant_ref_type</tt> serve for this purpose.
@@ -997,7 +997,7 @@ Here is an example of naming a delayed constant:
constant_type&lt;char&gt;::type space(constant(' '));
for_each(a.begin(),a.end(), cout &lt;&lt; space &lt;&lt; _1);
</pre>
</p></div><div class="simplesect"><div class="titlepage"><div><h4 class="title"><a name="id2793531"></a>About assignment and subscript operators</h4></div></div><p>
</p></div><div class="simplesect"><div class="titlepage"><div><h4 class="title"><a name="id2793541"></a>About assignment and subscript operators</h4></div></div><p>
As described in <a href="#sect:assignment_and_subscript" title="5.2.2. Assignment and subscript operators">Section 5.2.2</a>, assignment and subscripting operators are always defined as member functions.
This means, that for expressions of the form
<tt>x = y</tt> or <tt>x[y]</tt> to be interpreted as lambda expressions, the left-hand operand <tt>x</tt> must be a lambda expression.
@@ -1070,13 +1070,7 @@ for_each(a, a+5,
The BLL supports an alternative syntax for control expressions, suggested
by Joel de Guzmann.
By overloading the <tt>operator[]</tt> we can
get a closer resemblance with the built-in control structures.
For example, using this syntax the <tt>if_then</tt> example above
can be written as:
<pre class="programlisting">
for_each(a.begin(), a.end(),
if(_1 % 2 == 0)[ cout &lt;&lt; _1 ])
</pre>
get a closer resemblance with the built-in control structures:
<pre class="programlisting">
if_(condition)[then_part]
@@ -1086,6 +1080,13 @@ do_[body].while_(condition)
for_(init, condition, increment)[body]
</pre>
For example, using this syntax the <tt>if_then</tt> example above
can be written as:
<pre class="programlisting">
for_each(a.begin(), a.end(),
if(_1 % 2 == 0)[ cout &lt;&lt; _1 ])
</pre>
As more experience is gained, we may end up deprecating one or the other
of these syntaces.
@@ -1284,7 +1285,7 @@ objects related to creating and destroying objects,
showing the expression to create and call the function object,
and the effect of evaluating that expression.
</p><div class="table"><p><a name="table:constructor_destructor_fos"></a><b>Table 1. Construction and destruction related function objects.</b></p><table summary="Construction and destruction related function objects." border="1"><colgroup><col><col></colgroup><thead><tr><th>Function object call</th><th>Wrapped expression</th></tr></thead><tbody><tr><td><tt>constructor&lt;T&gt;()(<i><tt>arg_list</tt></i>)</tt></td><td>T(<i><tt>arg_list</tt></i>)</td></tr><tr><td><tt>destructor()(a)</tt></td><td><tt>a.~A()</tt>, where <tt>a</tt> is of type <tt>A</tt></td></tr><tr><td><tt>destructor()(pa)</tt></td><td><tt>pa.-&gt;A()</tt>, where <tt>pa</tt> is of type <tt>A*</tt></td></tr><tr><td><tt>new_ptr&lt;T&gt;()(<i><tt>arg_list</tt></i>)</tt></td><td><tt>new T(<i><tt>arg_list</tt></i>)</tt></td></tr><tr><td><tt>new_array&lt;T&gt;()(sz)</tt></td><td><tt>new T[sz]</tt></td></tr><tr><td><tt>delete_ptr()(p)</tt></td><td><tt>delete p</tt></td></tr><tr><td><tt>delete_array()(p)</tt></td><td><tt>delete p[]</tt></td></tr></tbody></table></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2794800"></a>5.9. Special lambda expressions</h3></div></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2794808"></a>5.9.1. Preventing argument substitution</h4></div></div><p>
</p><div class="table"><p><a name="table:constructor_destructor_fos"></a><b>Table 1. Construction and destruction related function objects.</b></p><table summary="Construction and destruction related function objects." border="1"><colgroup><col><col></colgroup><thead><tr><th>Function object call</th><th>Wrapped expression</th></tr></thead><tbody><tr><td><tt>constructor&lt;T&gt;()(<i><tt>arg_list</tt></i>)</tt></td><td>T(<i><tt>arg_list</tt></i>)</td></tr><tr><td><tt>destructor()(a)</tt></td><td><tt>a.~A()</tt>, where <tt>a</tt> is of type <tt>A</tt></td></tr><tr><td><tt>destructor()(pa)</tt></td><td><tt>pa.-&gt;A()</tt>, where <tt>pa</tt> is of type <tt>A*</tt></td></tr><tr><td><tt>new_ptr&lt;T&gt;()(<i><tt>arg_list</tt></i>)</tt></td><td><tt>new T(<i><tt>arg_list</tt></i>)</tt></td></tr><tr><td><tt>new_array&lt;T&gt;()(sz)</tt></td><td><tt>new T[sz]</tt></td></tr><tr><td><tt>delete_ptr()(p)</tt></td><td><tt>delete p</tt></td></tr><tr><td><tt>delete_array()(p)</tt></td><td><tt>delete p[]</tt></td></tr></tbody></table></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2794809"></a>5.9. Special lambda expressions</h3></div></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2794816"></a>5.9.1. Preventing argument substitution</h4></div></div><p>
When a lambda functor is called, the default behavior is to substitute
the actual arguments for the placeholders within all subexpressions.
@@ -1410,7 +1411,7 @@ int nested(const F&amp; f) {
}
</pre>
</p></div><div class="section"><div class="titlepage"><div><h5 class="title"><a name="id2795067"></a>5.9.1.2. Protect</h5></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h5 class="title"><a name="id2795076"></a>5.9.1.2. Protect</h5></div></div><p>
The <tt>protect</tt> function is related to unlambda.
It is also used to prevent the argument substitution taking place,
@@ -1515,7 +1516,7 @@ since calls to sub lambda functors are made inside the BLL,
and are not affected by the non-const rvalue problem.
</p></li></ol></div>
</p></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2795373"></a>5.10. Casts, sizeof and typeid</h3></div></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="sect:cast_expressions"></a>5.10.1.
</p></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2795382"></a>5.10. Casts, sizeof and typeid</h3></div></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="sect:cast_expressions"></a>5.10.1.
Cast expressions
</h4></div></div><p>
The BLL defines its counterparts for the four cast expressions
@@ -1544,7 +1545,7 @@ int count = 0;
for_each(a.begin(), a.end(),
if_then(ll_dynamic_cast&lt;derived*&gt;(_1), ++var(count)));
</pre>
</p></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2795475"></a>5.10.2. Sizeof and typeid</h4></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2795484"></a>5.10.2. Sizeof and typeid</h4></div></div><p>
The BLL counterparts for these expressions are named
<tt>ll_sizeof</tt> and <tt>ll_typeid</tt>.
@@ -1817,7 +1818,7 @@ public:
Note, that we are reusing the existing specializations for the
BLL <tt>return_type_2</tt> template,
which require that the argument types are references.
</p><div class="table"><p><a name="table:actions"></a><b>Table 2. Action types</b></p><table summary="Action types" border="1"><colgroup><col><col></colgroup><tbody><tr><td><tt>+</tt></td><td><tt>arithmetic_action&lt;plus_action&gt;</tt></td></tr><tr><td><tt>-</tt></td><td><tt>arithmetic_action&lt;minus_action&gt;</tt></td></tr><tr><td><tt>*</tt></td><td><tt>arithmetic_action&lt;multiply_action&gt;</tt></td></tr><tr><td><tt>/</tt></td><td><tt>arithmetic_action&lt;divide_action&gt;</tt></td></tr><tr><td><tt>%</tt></td><td><tt>arithmetic_action&lt;remainder_action&gt;</tt></td></tr><tr><td><tt>+</tt></td><td><tt>unary_arithmetic_action&lt;plus_action&gt;</tt></td></tr><tr><td><tt>-</tt></td><td><tt>unary_arithmetic_action&lt;minus_action&gt;</tt></td></tr><tr><td><tt>&amp;</tt></td><td><tt>bitwise_action&lt;and_action&gt;</tt></td></tr><tr><td><tt>|</tt></td><td><tt>bitwise_action&lt;or_action&gt;</tt></td></tr><tr><td><tt>~</tt></td><td><tt>bitwise_action&lt;not_action&gt;</tt></td></tr><tr><td><tt>^</tt></td><td><tt>bitwise_action&lt;xor_action&gt;</tt></td></tr><tr><td><tt>&lt;&lt;</tt></td><td><tt>bitwise_action&lt;leftshift_action_no_stream&gt;</tt></td></tr><tr><td><tt>&gt;&gt;</tt></td><td><tt>bitwise_action&lt;rightshift_action_no_stream&gt;</tt></td></tr><tr><td><tt>&amp;&amp;</tt></td><td><tt>logical_action&lt;and_action&gt;</tt></td></tr><tr><td><tt>||</tt></td><td><tt>logical_action&lt;or_action&gt;</tt></td></tr><tr><td><tt>!</tt></td><td><tt>logical_action&lt;not_action&gt;</tt></td></tr><tr><td><tt>&lt;</tt></td><td><tt>relational_action&lt;less_action&gt;</tt></td></tr><tr><td><tt>&gt;</tt></td><td><tt>relational_action&lt;greater_action&gt;</tt></td></tr><tr><td><tt>&lt;=</tt></td><td><tt>relational_action&lt;lessorequal_action&gt;</tt></td></tr><tr><td><tt>&gt;=</tt></td><td><tt>relational_action&lt;greaterorequal_action&gt;</tt></td></tr><tr><td><tt>==</tt></td><td><tt>relational_action&lt;equal_action&gt;</tt></td></tr><tr><td><tt>!=</tt></td><td><tt>relational_action&lt;notequal_action&gt;</tt></td></tr><tr><td><tt>+=</tt></td><td><tt>arithmetic_assignment_action&lt;plus_action&gt;</tt></td></tr><tr><td><tt>-=</tt></td><td><tt>arithmetic_assignment_action&lt;minus_action&gt;</tt></td></tr><tr><td><tt>*=</tt></td><td><tt>arithmetic_assignment_action&lt;multiply_action&gt;</tt></td></tr><tr><td><tt>/=</tt></td><td><tt>arithmetic_assignment_action&lt;divide_action&gt;</tt></td></tr><tr><td><tt>%=</tt></td><td><tt>arithmetic_assignment_action&lt;remainder_action&gt;</tt></td></tr><tr><td><tt>&amp;=</tt></td><td><tt>bitwise_assignment_action&lt;and_action&gt;</tt></td></tr><tr><td><tt>=|</tt></td><td><tt>bitwise_assignment_action&lt;or_action&gt;</tt></td></tr><tr><td><tt>^=</tt></td><td><tt>bitwise_assignment_action&lt;xor_action&gt;</tt></td></tr><tr><td><tt>&lt;&lt;=</tt></td><td><tt>bitwise_assignment_action&lt;leftshift_action&gt;</tt></td></tr><tr><td><tt>&gt;&gt;=</tt></td><td><tt>bitwise_assignment_action&lt;rightshift_action&gt;</tt></td></tr><tr><td><tt>++</tt></td><td><tt>pre_increment_decrement_action&lt;increment_action&gt;</tt></td></tr><tr><td><tt>--</tt></td><td><tt>pre_increment_decrement_action&lt;decrement_action&gt;</tt></td></tr><tr><td><tt>++</tt></td><td><tt>post_increment_decrement_action&lt;increment_action&gt;</tt></td></tr><tr><td><tt>--</tt></td><td><tt>post_increment_decrement_action&lt;decrement_action&gt;</tt></td></tr><tr><td><tt>&amp;</tt></td><td><tt>other_action&lt;address_of_action&gt;</tt></td></tr><tr><td><tt>*</tt></td><td><tt>other_action&lt;contents_of_action&gt;</tt></td></tr><tr><td><tt>,</tt></td><td><tt>other_action&lt;comma_action&gt;</tt></td></tr></tbody></table></div></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2796882"></a>7. Practical considerations</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2796888"></a>7.1. Performance</h3></div></div><p>In theory, all overhead of using STL algorithms and lambda functors
</p><div class="table"><p><a name="table:actions"></a><b>Table 2. Action types</b></p><table summary="Action types" border="1"><colgroup><col><col></colgroup><tbody><tr><td><tt>+</tt></td><td><tt>arithmetic_action&lt;plus_action&gt;</tt></td></tr><tr><td><tt>-</tt></td><td><tt>arithmetic_action&lt;minus_action&gt;</tt></td></tr><tr><td><tt>*</tt></td><td><tt>arithmetic_action&lt;multiply_action&gt;</tt></td></tr><tr><td><tt>/</tt></td><td><tt>arithmetic_action&lt;divide_action&gt;</tt></td></tr><tr><td><tt>%</tt></td><td><tt>arithmetic_action&lt;remainder_action&gt;</tt></td></tr><tr><td><tt>+</tt></td><td><tt>unary_arithmetic_action&lt;plus_action&gt;</tt></td></tr><tr><td><tt>-</tt></td><td><tt>unary_arithmetic_action&lt;minus_action&gt;</tt></td></tr><tr><td><tt>&amp;</tt></td><td><tt>bitwise_action&lt;and_action&gt;</tt></td></tr><tr><td><tt>|</tt></td><td><tt>bitwise_action&lt;or_action&gt;</tt></td></tr><tr><td><tt>~</tt></td><td><tt>bitwise_action&lt;not_action&gt;</tt></td></tr><tr><td><tt>^</tt></td><td><tt>bitwise_action&lt;xor_action&gt;</tt></td></tr><tr><td><tt>&lt;&lt;</tt></td><td><tt>bitwise_action&lt;leftshift_action_no_stream&gt;</tt></td></tr><tr><td><tt>&gt;&gt;</tt></td><td><tt>bitwise_action&lt;rightshift_action_no_stream&gt;</tt></td></tr><tr><td><tt>&amp;&amp;</tt></td><td><tt>logical_action&lt;and_action&gt;</tt></td></tr><tr><td><tt>||</tt></td><td><tt>logical_action&lt;or_action&gt;</tt></td></tr><tr><td><tt>!</tt></td><td><tt>logical_action&lt;not_action&gt;</tt></td></tr><tr><td><tt>&lt;</tt></td><td><tt>relational_action&lt;less_action&gt;</tt></td></tr><tr><td><tt>&gt;</tt></td><td><tt>relational_action&lt;greater_action&gt;</tt></td></tr><tr><td><tt>&lt;=</tt></td><td><tt>relational_action&lt;lessorequal_action&gt;</tt></td></tr><tr><td><tt>&gt;=</tt></td><td><tt>relational_action&lt;greaterorequal_action&gt;</tt></td></tr><tr><td><tt>==</tt></td><td><tt>relational_action&lt;equal_action&gt;</tt></td></tr><tr><td><tt>!=</tt></td><td><tt>relational_action&lt;notequal_action&gt;</tt></td></tr><tr><td><tt>+=</tt></td><td><tt>arithmetic_assignment_action&lt;plus_action&gt;</tt></td></tr><tr><td><tt>-=</tt></td><td><tt>arithmetic_assignment_action&lt;minus_action&gt;</tt></td></tr><tr><td><tt>*=</tt></td><td><tt>arithmetic_assignment_action&lt;multiply_action&gt;</tt></td></tr><tr><td><tt>/=</tt></td><td><tt>arithmetic_assignment_action&lt;divide_action&gt;</tt></td></tr><tr><td><tt>%=</tt></td><td><tt>arithmetic_assignment_action&lt;remainder_action&gt;</tt></td></tr><tr><td><tt>&amp;=</tt></td><td><tt>bitwise_assignment_action&lt;and_action&gt;</tt></td></tr><tr><td><tt>=|</tt></td><td><tt>bitwise_assignment_action&lt;or_action&gt;</tt></td></tr><tr><td><tt>^=</tt></td><td><tt>bitwise_assignment_action&lt;xor_action&gt;</tt></td></tr><tr><td><tt>&lt;&lt;=</tt></td><td><tt>bitwise_assignment_action&lt;leftshift_action&gt;</tt></td></tr><tr><td><tt>&gt;&gt;=</tt></td><td><tt>bitwise_assignment_action&lt;rightshift_action&gt;</tt></td></tr><tr><td><tt>++</tt></td><td><tt>pre_increment_decrement_action&lt;increment_action&gt;</tt></td></tr><tr><td><tt>--</tt></td><td><tt>pre_increment_decrement_action&lt;decrement_action&gt;</tt></td></tr><tr><td><tt>++</tt></td><td><tt>post_increment_decrement_action&lt;increment_action&gt;</tt></td></tr><tr><td><tt>--</tt></td><td><tt>post_increment_decrement_action&lt;decrement_action&gt;</tt></td></tr><tr><td><tt>&amp;</tt></td><td><tt>other_action&lt;address_of_action&gt;</tt></td></tr><tr><td><tt>*</tt></td><td><tt>other_action&lt;contents_of_action&gt;</tt></td></tr><tr><td><tt>,</tt></td><td><tt>other_action&lt;comma_action&gt;</tt></td></tr></tbody></table></div></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2796890"></a>7. Practical considerations</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2796897"></a>7.1. Performance</h3></div></div><p>In theory, all overhead of using STL algorithms and lambda functors
compared to hand written loops can be optimized away, just as the overhead
from standard STL function objects and binders can.
@@ -1887,7 +1888,7 @@ Note however, that evaluating a lambda functor consist of a sequence of calls to
If the compiler fails to actually expand these functions inline,
the performance can suffer.
The running time can more than double if this happens.
Although the above tests do not include such an expression, we have experiensed
Although the above tests do not include such an expression, we have experienced
this for some seemingly simple expressions.
@@ -1909,7 +1910,7 @@ The running times are expressed in arbitrary units." border="1"><colgroup><col><
</p><p>Some additional performance testing with an earlier version of the
library is described
[<a href="#cit:jarvi:00" title="[Jär00]">Jär00</a>].
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2797381"></a>7.2. About compiling</h3></div></div><p>The BLL uses templates rather heavily, performing numerous recursive instantiations of the same templates.
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2797390"></a>7.2. About compiling</h3></div></div><p>The BLL uses templates rather heavily, performing numerous recursive instantiations of the same templates.
This has (at least) three implications:
<div class="itemizedlist"><ul type="disc"><li><p>
While it is possible to write incredibly complex lambda expressions, it probably isn't a good idea.
@@ -1923,7 +1924,7 @@ This can make the error messages very long and difficult to interpret, particula
The C++ Standard suggests a template nesting level of 17 to help detect infinite recursion.
Complex lambda templates can easily exceed this limit.
Most compilers allow a greater number of nested templates, but commonly require the limit explicitly increased with a command line argument.
</p></li></ul></div></p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2797442"></a>7.3. Portability</h3></div></div><p>
</p></li></ul></div></p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2797451"></a>7.3. Portability</h3></div></div><p>
The BLL works with the following compilers, that is, the compilers are capable of compiling the test cases that are included with the BLL:
<div class="itemizedlist"><ul type="disc"><li>GCC 3.0.4
@@ -1932,7 +1933,7 @@ The BLL works with the following compilers, that is, the compilers are capable o
)
</li></ul></div>
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2797482"></a>7.3.1. Test coverage</h4></div></div><p>The following list describes the test files included and the features that each file covers:
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2797490"></a>7.3.1. Test coverage</h4></div></div><p>The following list describes the test files included and the features that each file covers:
<div class="itemizedlist"><ul type="disc"><li><p>
<tt>bind_tests_simple.cpp</tt> : Bind expressions of different arities and types of target functions: function pointers, function objects and member functions.
@@ -1978,7 +1979,7 @@ Contains several user defined operators and the corresponding specializations fo
Contains tests for using <tt>boost::function</tt> together with lambda functors.
</p></li></ul></div>
</p></div></div></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2797826"></a>8. Relation to other Boost libraries</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2797834"></a>8.1. Boost Function</h3></div></div><p>Sometimes it is convenient to store lambda functors in variables.
</p></div></div></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2797835"></a>8. Relation to other Boost libraries</h2></div></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2797842"></a>8.1. Boost Function</h3></div></div><p>Sometimes it is convenient to store lambda functors in variables.
However, the types of even the simplest lambda functors are long and unwieldy, and it is in general unfeasible to declare variables with lambda functor types.
<span class="emphasis"><i>The Boost Function library</i></span> [<a href="#cit:boost::function" title="[function]">function</a>] defines wrappers for arbitrary function objects, for example
lambda functors; and these wrappers have types that are easy to type out.
@@ -1986,14 +1987,14 @@ lambda functors; and these wrappers have types that are easy to type out.
For example:
<pre class="programlisting">
boost::function&lt;int, int, int&gt; f = _1 + _2;
boost::function&lt;int&amp;, int&amp;&gt; g = unlambda(_1 += 10);
boost::function&lt;int(int, int)&gt; f = _1 + _2;
boost::function&lt;int&amp;(int&amp;)&gt; g = (_1 += 10);
int i = 1, j = 2;
f(i); // returns 3
g(i); // sets i to = 11;
</pre>
The return and parameter types of the wrapped function object must be written explicilty as template arguments to the wrapper template <tt>boost::function</tt>; even when lambda functors, which otherwise have generic parameters, are wrapped.
The return and parameter types of the wrapped function object must be written explicilty as the template argument to the wrapper template <tt>boost::function</tt>; even when lambda functors, which otherwise have generic parameters, are wrapped.
Wrapping a function object with <tt>boost::function</tt> introduces a performance cost comparable to virtual function dispatch, though virtual functions are not actually used.
Note that storing lambda functors inside <tt>boost::function</tt>
@@ -2011,13 +2012,13 @@ For example:
<pre class="programlisting">
int* sum = new int();
*sum = 0;
boost::function&lt;int&amp;, int&gt; counter = *sum += _1;
boost::function&lt;int&amp;(int)&gt; counter = *sum += _1;
counter(5); // ok, *sum = 5;
delete sum;
counter(3); // error, *sum does not exist anymore
</pre>
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2797938"></a>8.2. Boost Bind</h3></div></div><p>
</p></div><div class="section"><div class="titlepage"><div><h3 class="title"><a name="id2797946"></a>8.2. Boost Bind</h3></div></div><p>
<span class="emphasis"><i>The Boost Bind</i></span> [<a href="#cit:boost::bind" title="[bind]">bind</a>] library has partially overlapping functionality with the BLL.
Basically, the Boost Bind library (BB in the sequel) implements the bind expression part of BLL.
There are, however, some semantical differerences.
@@ -2036,7 +2037,7 @@ a larger set of compilers.
</p><p>
The following two sections describe what are the semantic differences
between the bind expressions in BB and BLL.
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2798003"></a>8.2.1. First argument of bind expression</h4></div></div>
</p><div class="section"><div class="titlepage"><div><h4 class="title"><a name="id2798011"></a>8.2.1. First argument of bind expression</h4></div></div>
In BB the first argument of the bind expression, the target function,
is treated differently from the other arguments,
@@ -2094,7 +2095,7 @@ performance hit, particularly for the simplest (and thus the most common)
lambda functors.
We are working on a hybrid approach, which will allow more placeholders
but not compromise the performance of simple lambda functors.
</p></div></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2798134"></a>9. Contributors</h2></div></div>
</p></div></div><div class="section"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="id2798126"></a>9. Contributors</h2></div></div>
The main body of the library was written by Jaakko Järvi and Gary Powell.
We've got outside help, suggestions and ideas from Jeremy Siek, Peter Higley, Peter Dimov, Valentin Bonnard, William Kempf.
@@ -2102,7 +2103,7 @@ We would particularly like to mention Joel de Guzmann and his work with
Phoenix which has influenced BLL significantly, making it considerably simpler
to extend the library with new features.
</div><div class="appendix"><h2 class="title" style="clear: both"><a name="id2798156"></a>A. Rationale for some of the design decisions</h2><div class="section"><div class="titlepage"><div><h3 class="title"><a name="sect:why_weak_arity"></a>1.
</div><div class="appendix"><h2 class="title" style="clear: both"><a name="id2798147"></a>A. Rationale for some of the design decisions</h2><div class="section"><div class="titlepage"><div><h3 class="title"><a name="sect:why_weak_arity"></a>1.
Lambda functor arity
</h3></div></div><p>
The highest placeholder index in a lambda expression determines the arity of the resulting function object.
@@ -2155,7 +2156,7 @@ the error would go unnoticed.
Furthermore, weak arity checking simplifies the implementation a bit.
Following the recommendation of the Boost review, strict arity checking
was dropped.
</p></div></div><div id="id2798308" class="bibliography"><div class="titlepage"><div><h2 class="title"><a name="id2798308"></a>Bibliography</h2></div></div><div class="biblioentry"><a name="cit:stepanov:94"></a><p>[STL94] <span class="authorgroup">A. A. Stepanov and M. Lee. </span><span class="title"><I>The Standard Template Library</I>. </span><span class="orgname">Hewlett-Packard Laboratories. </span><span class="pubdate">1994. </span><span class="bibliomisc">
</p></div></div><div id="id2798300" class="bibliography"><div class="titlepage"><div><h2 class="title"><a name="id2798300"></a>Bibliography</h2></div></div><div class="biblioentry"><a name="cit:stepanov:94"></a><p>[STL94] <span class="authorgroup">A. A. Stepanov and M. Lee. </span><span class="title"><I>The Standard Template Library</I>. </span><span class="orgname">Hewlett-Packard Laboratories. </span><span class="pubdate">1994. </span><span class="bibliomisc">
<a href="http://www.hpl.hp.com/techreports" target="_top">www.hpl.hp.com/techreports</a>
. </span></p></div><div class="biblioentry"><a name="cit:sgi:02"></a><p>[SGI02] <span class="title"><I>The SGI Standard Template Library</I>. </span><span class="pubdate">2002. </span><span class="bibliomisc"><a href="http://www.sgi.com/tech/stl/" target="_top">www.sgi.com/tech/stl/</a>. </span></p></div><div class="biblioentry"><a name="cit:c++:98"></a><p>[C++98] <span class="title"><I>International Standard, Programming Languages &#8211; C++</I>. </span><span class="subtitle">ISO/IEC:14882. </span><span class="pubdate">1998. </span></p></div><div class="biblioentry"><a name="cit:jarvi:99"></a><p>[Jär99] <span class="articleinfo">
<span class="author">Jaakko Järvi. </span>
@@ -2166,7 +2167,7 @@ was dropped.
. </span><span class="pubdate">2002. </span></p></div><div class="biblioentry"><a name="cit:boost::bind"></a><p>[bind] <span class="title"><I>Boost Bind Library</I>. </span><span class="bibliomisc"><a href="http://www.boost.org/libs/bind/bind.html" target="_top">www.boost.org/libs/bind/bind.html</a>
. </span><span class="pubdate">2002. </span></p></div><div class="biblioentry"><a name="cit:boost::function"></a><p>[function] <span class="title"><I>Boost Function Library</I>. </span><span class="bibliomisc"><a href="http://www.boost.org/libs/function/" target="_top">www.boost.org/libs/function/</a>
. </span><span class="pubdate">2002. </span></p></div><div class="biblioentry"><a name="cit:fc++"></a><p>[fc++] <span class="title"><I>The FC++ library: Functional Programming in C++</I>. </span><span class="author">Yannis Smaragdakis. </span><span class="author">Brian McNamara. </span><span class="bibliomisc"><a href="http://www.cc.gatech.edu/~yannis/fc++/" target="_top">www.cc.gatech.edu/~yannis/fc++/</a>
. </span><span class="pubdate">2002. </span></p></div></div><div class="footnotes"><br><hr width="100" align="left"><div class="footnote"><p><sup>[<a name="ftn.id2729061" href="#id2729061">1</a>] </sup>
. </span><span class="pubdate">2002. </span></p></div></div><div class="footnotes"><br><hr width="100" align="left"><div class="footnote"><p><sup>[<a name="ftn.id2729070" href="#id2729070">1</a>] </sup>
Strictly taken, the C++ standard defines <tt>for_each</tt> as a <span class="emphasis"><i>non-modifying sequence operation</i></span>, and the function object passed to <tt>for_each</tt> should not modify its argument.
The requirements for the arguments of <tt>for_each</tt> are unnecessary strict, since as long as the iterators are <span class="emphasis"><i>mutable</i></span>, <tt>for_each</tt> accepts a function object that can have side-effects on their argument.
Nevertheless, it is straightforward to provide another function template with the functionality of<tt>std::for_each</tt> but more fine-grained requirements for its arguments.

0
dummy
View File

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@@ -20,7 +20,7 @@
#include <algorithm>
#include <iterator> // for iterator_traits
#include <utilities> // for std::pair
#include <utility> // for std::pair
namespace boost {
namespace lambda {
@@ -154,11 +154,11 @@ struct count {
template <class Args>
struct sig {
typename ::std::iterator_traits<
typedef typename boost::remove_const<
typedef typename ::std::iterator_traits<
typename boost::remove_const<
typename boost::tuples::element<1, Args>::type
>::type
>::difference_type type
>::difference_type type;
};
template <class A, class B >
@@ -173,11 +173,11 @@ struct count_if {
template <class Args>
struct sig {
typename ::std::iterator_traits<
typedef typename boost::remove_const<
typedef typename ::std::iterator_traits<
typename boost::remove_const<
typename boost::tuples::element<1, Args>::type
>::type
>::difference_type type
>::difference_type type;
};
template <class A, class B, class C >
@@ -610,7 +610,7 @@ struct unique_copy {
template <class A, class B, class C, class D>
C
operator()(A a, B b, C c, D c) const
operator()(A a, B b, C c, D d) const
{ return ::std::unique_copy(a, b, c, d); }
};
@@ -678,7 +678,7 @@ struct rotate_copy {
template <class A, class B, class C, class D>
C
operator()(A a, B b, C c, D c) const
operator()(A a, B b, C c, D d) const
{ return ::std::rotate_copy(a, b, c, d); }
};

View File

@@ -1,6 +1,6 @@
// - casts.hpp -- BLambda Library -------------
//
// Copyright (C) 2000 Gary Powell (gary.powell@sierra.com)
// Copyright (C) 2000 Gary Powell (powellg@amazon.com)
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
//
// Permission to copy, use, sell and distribute this software is granted

View File

@@ -1,6 +1,6 @@
// - construct.hpp -- Lambda Library -------------
//
// Copyright (C) 2000 Gary Powell (gary.powell@sierra.com)
// Copyright (C) 2000 Gary Powell (powellg@amazon.com)
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
//
// Permission to copy, use, sell and distribute this software is granted

View File

@@ -1,4 +1,18 @@
// -- core.hpp -- Boost Lambda Library -------------------------------------
//
// Copyright (C) 2000 Gary Powell (powellg@amazon.com)
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
//
// Includes the core of LL, without any real features for client:
//

View File

@@ -1,7 +1,7 @@
// Boost Lambda Library -- control_constructs_common.hpp -------------------
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000 Gary Powell (gary.powell@sierra.com)
// Copyright (C) 2000 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.

View File

@@ -1,7 +1,7 @@
// Boost Lambda Library -- control_structures_impl.hpp ---------------------
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000 Gary Powell (gary.powell@sierra.com)
// Copyright (C) 2000 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.

View File

@@ -345,6 +345,7 @@ struct function_adaptor<Result (Object::*)(Arg1, Arg2, Arg3) const> {
template <class Object, class Arg1, class Arg2, class Arg3, class Result>
struct function_adaptor<Result (Object::*)(Arg1, Arg2, Arg3)> {
template<class T> struct sig { typedef Result type; };
template <class RET, class A1, class A2, class A3>
static Result apply( Result (Object::*func)(Arg1, Arg2, Arg3), Object* o, A1& a1, A2& a2, A3& a3) {
return (o->*func)(a1, a2, a3);

View File

@@ -436,10 +436,10 @@ namespace detail {
template<class RET, class A, class B>
class member_pointer_caller {
A a;
B b;
A a; B b;
public:
member_pointer_caller(A aa, B bb) : a(aa), b(bb) {}
member_pointer_caller(const A& aa, const B& bb) : a(aa), b(bb) {}
RET operator()() const { return (a->*b)(); }
@@ -589,29 +589,24 @@ struct member_pointer_action_helper<false, true> {
template<class RET, class A, class B>
static RET apply(A& a, B& b) {
typedef typename ::boost::remove_cv<B>::type plainB;
typedef typename detail::member_pointer<plainB>::type ret_t;
typedef typename ::boost::remove_cv<A>::type plainA;
// we always add const (it is just the pointer types, not the types
// pointed to) to make the to routes (calling and type deduction)
// we always strip cv:s to
// make the two routes (calling and type deduction)
// to give the same results (and the const does not make any functional
// difference)
return detail::member_pointer_caller<ret_t, const A&, const B&>(a, b);
return detail::member_pointer_caller<ret_t, plainA, plainB>(a, b);
}
template<class A, class B>
struct return_type {
typedef typename detail::remove_reference_and_cv<B>::type plainB;
typedef typename detail::member_pointer<plainB>::type ret_t;
typedef typename detail::remove_reference_and_cv<A>::type plainA;
// we always add const (it is just the pointer types, not the types
// pointed to)
typedef detail::member_pointer_caller<
ret_t,
typename boost::add_reference<const A>::type,
typename boost::add_reference<const B>::type
> type;
typedef detail::member_pointer_caller<ret_t, plainA, plainB> type;
};
};
@@ -621,12 +616,10 @@ template<> class other_action<member_pointer_action> {
public:
template<class RET, class A, class B>
static RET apply(A& a, B& b) {
typedef typename
::boost::remove_cv<B>::type plainB;
return
detail::member_pointer_action_helper<
return detail::member_pointer_action_helper<
boost::is_pointer<A>::value &&
detail::member_pointer<plainB>::is_data_member,
boost::is_pointer<A>::value &&

View File

@@ -492,7 +492,6 @@ struct promotion_of_unsigned_int
{
typedef
detail::IF<sizeof(long) <= sizeof(unsigned int),
// I had the logic reversed but ">" messes up the parsing.
unsigned long,
long>::RET type;
};
@@ -866,10 +865,20 @@ namespace std {
template <class Key, class T, class Cmp, class Allocator> class map;
template <class Key, class T, class Cmp, class Allocator> class multimap;
template <class T, class Allocator> class vector;
template <class T, class Allocator> class deque;
template <class Char, class Traits, class Allocator> class basic_string;
}
// The GCC 2.95.x uses a non-conformant deque
#if BOOST_WORKAROUND(__GNUC__, == 2) && __GNUC_MINOR__ <= 96
#include <deque>
#else
namespace std {
template <class T, class Allocator> class deque;
}
#endif
namespace boost {
namespace lambda {

View File

@@ -1,7 +1,7 @@
// Boost Lambda Library -- if.hpp ------------------------------------------
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000 Gary Powell (gary.powell@sierra.com)
// Copyright (C) 2000 Gary Powell (powellg@amazon.com)
// Copyright (C) 2001-2002 Joel de Guzman
//
// Permission to copy, use, sell and distribute this software is granted

View File

@@ -1,7 +1,7 @@
// Boost Lambda Library -- loops.hpp ----------------------------------------
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000 Gary Powell (gary.powell@sierra.com)
// Copyright (C) 2000 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.

View File

@@ -1,6 +1,6 @@
// Boost Lambda Library -- switch.hpp -----------------------------------
//
// Copyright (C) 2000 Gary Powell (gary.powell@sierra.com)
// Copyright (C) 2000 Gary Powell (powellg@amazon.com)
// Copyright (C) 1999, 2000 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
//
// Permission to copy, use, sell and distribute this software is granted

View File

@@ -1,4 +1,21 @@
// bind_tests_advanced.cpp --------------------------------
// bind_tests_advanced.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,4 +1,21 @@
// bind_tests_simple.cpp --------------------------------
// bind_tests_simple.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"
@@ -31,6 +48,18 @@ class A {
public:
A(int n) : i(n) {};
int add(const int& j) { return i + j; }
int add2(int a1, int a2) { return i + a1 + a2; }
int add3(int a1, int a2, int a3) { return i + a1 + a2 + a3; }
int add4(int a1, int a2, int a3, int a4) { return i + a1 + a2 + a3 + a4; }
int add5(int a1, int a2, int a3, int a4, int a5)
{ return i + a1 + a2 + a3 + a4 + a5; }
int add6(int a1, int a2, int a3, int a4, int a5, int a6)
{ return i + a1 + a2 + a3 + a4 + a5 + a6; }
int add7(int a1, int a2, int a3, int a4, int a5, int a6, int a7)
{ return i + a1 + a2 + a3 + a4 + a5 + a6 + a7; }
int add8(int a1, int a2, int a3, int a4, int a5, int a6, int a7, int a8)
{ return i + a1 + a2 + a3 + a4 + a5 + a6 + a7 + a8; }
};
void test_member_functions()
@@ -47,6 +76,14 @@ void test_member_functions()
BOOST_TEST(bind(&A::add, _1, 1)(a) == 11);
BOOST_TEST(bind(&A::add, _1, 1)(make_const(&a)) == 11);
BOOST_TEST(bind(&A::add2, _1, 1, 1)(a) == 12);
BOOST_TEST(bind(&A::add3, _1, 1, 1, 1)(a) == 13);
BOOST_TEST(bind(&A::add4, _1, 1, 1, 1, 1)(a) == 14);
BOOST_TEST(bind(&A::add5, _1, 1, 1, 1, 1, 1)(a) == 15);
BOOST_TEST(bind(&A::add6, _1, 1, 1, 1, 1, 1, 1)(a) == 16);
BOOST_TEST(bind(&A::add7, _1, 1, 1, 1, 1, 1, 1, 1)(a) == 17);
BOOST_TEST(bind(&A::add8, _1, 1, 1, 1, 1, 1, 1, 1, 1)(a) == 18);
// This should fail, as lambda functors store arguments as const
// bind(&A::add, a, _1);
}

View File

@@ -1,4 +1,21 @@
// bind_tests_simple.cpp --------------------------------
// bind_tests_simple.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,4 +1,18 @@
// bll_and_function.cpp --------------------------------
// bll_and_function.cpp - The Boost Lambda Library -----------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// test using BLL and boost::function
@@ -21,13 +35,13 @@ using namespace std;
void test_function() {
boost::function<int, int, int> f;
boost::function<int (int, int)> f;
f = _1 + _2;
BOOST_TEST(f(1, 2)== 3);
int i=1; int j=2;
boost::function<int&, int&, int> g = _1 += _2;
boost::function<int& (int&, int)> g = _1 += _2;
g(i, j);
BOOST_TEST(i==3);
@@ -35,7 +49,7 @@ void test_function() {
int* sum = new int();
*sum = 0;
boost::function<int&, int> counter = *sum += _1;
boost::function<int& (int)> counter = *sum += _1;
counter(5); // ok, sum* = 5;
BOOST_TEST(*sum == 5);
delete sum;

View File

@@ -1,4 +1,21 @@
// cast_tests.cpp --------------------------------
// cast_tests.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,4 +1,21 @@
// constructor_tests.cpp --------------------------------
// constructor_tests.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,3 +1,21 @@
// -- control_structures.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,3 +1,21 @@
// -- exception_test.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,4 +1,21 @@
// extending_return_type_traits.cpp --------------------------------
// extending_return_type_traits.cpp -- The Boost Lambda Library --------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,4 +1,21 @@
// is_convertible_to_template_test.cpp ----------------------------
// is_instance_of_test.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,4 +1,21 @@
// member_pointer_test.cpp --------------------------------
// member_pointer_test.cpp -- The Boost Lambda Library ------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,4 +1,21 @@
// operator_tests_simple.cpp --------------------------------
// operator_tests_simple.cpp -- The Boost Lambda Library ---------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"

View File

@@ -1,4 +1,21 @@
// phoenix_style_control_structures.cpp --------------------------------
// phoenix_style_control_structures.cpp -- The Boost Lambda Library ------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"
@@ -21,11 +38,9 @@ using namespace boost::lambda;
using namespace std;
///////////////////////////////////////////////////////////////////////////////
//
// If-else, while, do-while, for tatements
//
///////////////////////////////////////////////////////////////////////////////
// If-else, while, do-while, for statements
int test_main(int, char *[]) {

View File

@@ -1,4 +1,21 @@
// switch_test.cpp --------------------------------
// switch_test.cpp -- The Boost Lambda Library --------------------------
//
// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
//
// Permission to copy, use, sell and distribute this software is granted
// provided this copyright notice appears in all copies.
// Permission to modify the code and to distribute modified code is granted
// provided this copyright notice appears in all copies, and a notice
// that the code was modified is included with the copyright notice.
//
// This software is provided "as is" without express or implied warranty,
// and with no claim as to its suitability for any purpose.
//
// For more information, see www.boost.org
// -----------------------------------------------------------------------
#define BOOST_INCLUDE_MAIN // for testing, include rather than link
#include <boost/test/test_tools.hpp> // see "Header Implementation Option"