From 51d60a603590d559647283bbf3d9c33ebf866002 Mon Sep 17 00:00:00 2001
From: "Ralf W. Grosse-Kunstleve" <rwgk@yahoo.com>
Date: Sat, 3 Mar 2001 11:48:52 +0000
Subject: [PATCH] added: converters for [plain] char and std::complex

[SVN r9397]
---
 include/boost/python/conversions.hpp | 39 ++++++++++++++++++++++++++++
 src/conversions.cpp                  | 21 +++++++++++++++
 test/comprehensive.cpp               | 34 ++++++++++++++++++++++++
 test/comprehensive.py                | 33 +++++++++++++++++++++++
 4 files changed, 127 insertions(+)

diff --git a/include/boost/python/conversions.hpp b/include/boost/python/conversions.hpp
index d11f7f14..b633c0ee 100644
--- a/include/boost/python/conversions.hpp
+++ b/include/boost/python/conversions.hpp
@@ -5,6 +5,9 @@
 //
 //  The author gratefully acknowleges the support of Dragon Systems, Inc., in
 //  producing this work.
+//
+// Revision History:
+// Mar 03 01  added: converters for [plain] char and std::complex (Ralf W. Grosse-Kunstleve)
 
 #ifndef METHOD_DWA122899_H_
 # define METHOD_DWA122899_H_
@@ -16,6 +19,7 @@
 # include <boost/smart_ptr.hpp>
 # include <boost/python/errors.hpp>
 # include <string>
+# include <complex>
 
 BOOST_PYTHON_BEGIN_CONVERSION_NAMESPACE // this is a gcc 2.95.2 bug workaround
 
@@ -100,6 +104,10 @@ PyObject* to_python(unsigned short);
 unsigned short from_python(PyObject*, boost::python::type<unsigned short>);
 unsigned short from_python(PyObject*, boost::python::type<const unsigned short&>);
 
+PyObject* to_python(char);
+char from_python(PyObject*, boost::python::type<char>);
+char from_python(PyObject*, boost::python::type<const char&>);
+
 PyObject* to_python(signed char);
 signed char from_python(PyObject*, boost::python::type<signed char>);
 signed char from_python(PyObject*, boost::python::type<const signed char&>);
@@ -130,6 +138,32 @@ PyObject* to_python(const std::string& s);
 std::string from_python(PyObject*, boost::python::type<std::string>);
 std::string from_python(PyObject*, boost::python::type<const std::string&>);
 
+template <class T>
+PyObject* to_python(const std::complex<T>& sc) {
+    Py_complex pcc;
+    pcc.real = sc.real();
+    pcc.imag = sc.imag();
+    return PyComplex_FromCComplex(pcc);
+}
+
+template <class T>
+std::complex<T> from_python(PyObject* p,
+                            boost::python::type<const std::complex<T>&>) {
+    if (! PyComplex_Check(p)) {
+      PyErr_SetString(PyExc_TypeError, "expected a complex number");
+      throw boost::python::argument_error();
+    }
+    return std::complex<T>(
+      static_cast<T>(PyComplex_RealAsDouble(p)),
+      static_cast<T>(PyComplex_ImagAsDouble(p)));
+}
+
+template <class T>
+inline std::complex<T> from_python(PyObject* p,
+                                   boost::python::type<std::complex<T> >) {
+    return from_python(p, boost::python::type<const std::complex<T>&>());
+}
+
 // For when your C++ function really wants to pass/return a PyObject*
 PyObject* to_python(PyObject*);
 PyObject* from_python(PyObject*, boost::python::type<PyObject*>);
@@ -304,6 +338,11 @@ inline unsigned short from_python(PyObject* p, boost::python::type<const unsigne
     return from_python(p, boost::python::type<unsigned short>());
 }
 
+inline char from_python(PyObject* p, boost::python::type<const char&>)
+{
+    return from_python(p, boost::python::type<char>());
+}
+
 inline signed char from_python(PyObject* p, boost::python::type<const signed char&>)
 {
     return from_python(p, boost::python::type<signed char>());
diff --git a/src/conversions.cpp b/src/conversions.cpp
index ded01e0e..369f197a 100644
--- a/src/conversions.cpp
+++ b/src/conversions.cpp
@@ -5,6 +5,9 @@
 //
 //  The author gratefully acknowleges the support of Dragon Systems, Inc., in
 //  producing this work.
+//
+// Revision History:
+// Mar 03 01  added: converters for [plain] char (Ralf W. Grosse-Kunstleve)
 
 #include <boost/python/conversions.hpp>
 #include <typeinfo>
@@ -160,6 +163,24 @@ unsigned short from_python(PyObject* p, boost::python::type<unsigned short> type
     return integer_from_python(p, type);
 }
 
+PyObject* to_python(char c)
+{
+    if (c == '\0') return PyString_FromString("");
+    return PyString_FromStringAndSize(&c, 1);
+}
+
+char from_python(PyObject* p, boost::python::type<char>)
+{
+    int l = -1;
+    if (PyString_Check(p)) l = PyString_Size(p);
+    if (l < 0 || l > 1) {
+        PyErr_SetString(PyExc_TypeError, "expected string of length 0 or 1");
+        throw boost::python::argument_error();
+    }
+    if (l == 0) return '\0';
+    return PyString_AsString(p)[0];
+}
+
 PyObject* to_python(unsigned char i)
 {
 	return integer_to_python(i);
diff --git a/test/comprehensive.cpp b/test/comprehensive.cpp
index 7fad74bb..592b0ebd 100644
--- a/test/comprehensive.cpp
+++ b/test/comprehensive.cpp
@@ -815,6 +815,25 @@ namespace bpl_test {
           w.set_secret_number(number);
   }
 
+  // Test plain char converters.
+  char get_plain_char() { return 'x'; }
+  std::string use_plain_char(char c) { return std::string(3, c); }
+  std::string use_const_plain_char(const char c) { return std::string(5, c); }
+
+  // Test std::complex<double> converters.
+  std::complex<double> dpolar(double rho, double theta) {
+    return std::polar(rho, theta);
+  }
+  double dreal(const std::complex<double>& c) { return c.real(); }
+  double dimag(std::complex<double> c) { return c.imag(); }
+
+  // Test std::complex<float> converters.
+  std::complex<float> fpolar(float rho, float theta) {
+    return std::polar(rho, theta);
+  }
+  double freal(const std::complex<float>& c) { return c.real(); }
+  double fimag(std::complex<float> c) { return c.imag(); }
+
 /************************************************************/
 /*                                                          */
 /*                       init the module                    */
@@ -1036,6 +1055,21 @@ void init_module(boost::python::module_builder& m)
     world_class.def(world_getinitargs, "__getinitargs__");
     world_class.def(world_getstate, "__getstate__");
     world_class.def(world_setstate, "__setstate__");
+
+    // Test plain char converters.
+    m.def(get_plain_char, "get_plain_char");
+    m.def(use_plain_char, "use_plain_char");
+    m.def(use_const_plain_char, "use_const_plain_char");
+
+    // Test std::complex<double> converters.
+    m.def(dpolar, "dpolar");
+    m.def(dreal, "dreal");
+    m.def(dimag, "dimag");
+
+    // Test std::complex<float> converters.
+    m.def(fpolar, "fpolar");
+    m.def(freal, "freal");
+    m.def(fimag, "fimag");
 }
 
 PyObject* raw(const boost::python::tuple& args, const boost::python::dictionary& keywords)
diff --git a/test/comprehensive.py b/test/comprehensive.py
index a8e181d2..8bc8021c 100644
--- a/test/comprehensive.py
+++ b/test/comprehensive.py
@@ -1070,6 +1070,39 @@ test methodologies for wrapping functions that return a pointer
     3
     >>> eo.second
     1
+
+======== test [plain] char converters ==============
+    >>> get_plain_char()
+    'x'
+    >>> use_plain_char('a')
+    'aaa'
+    >>> use_const_plain_char('b')
+    'bbbbb'
+
+======== test std::complex converters ==============
+    >>> c = dpolar(3, 5)
+    >>> type(c)
+    <type 'complex'>
+    >>> '%.3g' % (dreal(c))
+    '0.851'
+    >>> '%.3g' % (dimag(c))
+    '-2.88'
+    >>> '%.3g' % (freal(c))
+    '0.851'
+    >>> '%.3g' % (fimag(c))
+    '-2.88'
+    >>> c = fpolar(7, 13)
+    >>> type(c)
+    <type 'complex'>
+    >>> '%.3g' % (fimag(c))
+    '2.94'
+    >>> '%.3g' % (freal(c))
+    '6.35'
+    >>> '%.3g' % (dimag(c))
+    '2.94'
+    >>> '%.3g' % (dreal(c))
+    '6.35'
+
 '''
 
 from test import *