wave/ChangeLog

Boost.Wave: A Standard compliant C++ preprocessor library
http://www.boost.org/

Copyright (c) 2001-2007 Hartmut Kaiser. Distributed under the Boost
Software License, Version 1.0. (See accompanying file
LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-------------------------------------------------------------------------------

TODO (known issues):
- Fix expansion of macros, which replacement-list terminates in a partial 
  macro expansion.
- Fix the re2c lexer for iterators others then string::iterator (or more 
  generally for iterators, which aren't random access iterators)
- Try to remove the second parameter from the pp_iterator<>::force_include
  function.
- Fix the trigraph backslash problem in the re2c (C/C++ and IDL) scanners, if 
  there is the end of the (internal) buffer just in between a '??/' and a '\n'.
- Change the cpp_exception::what() function to return more meaningful error 
  texts.
  
- Do a sourceforge release.

-------------------------------------------------------------------------------

CHANGELOG

- Wave Version 1.3
- Changed the return value of the 'evaluated_conditional_expression()' pp hook
  to 'bool' allowing to force Wave to re-evaluate the current conditional
  expression. This was suggested by Felipe Magno de Almeida.
- Added a wave::context object as first parameter to all pp hook functions. 
  This is an interface compatibility breaking change. The new pp-hooks can be 
  disabled by defining the BOOST_WAVE_USE_DEPRECIATED_PREPROCESSING_HOOKS 
  compile time constant to something not equal to zero. By default this 
  constant will be defined to zero for Boost V1.35.0 and newer, switching to
  the new interface by default.
- Added optional support for the import keyword (needed for the C++ module
  proposal). The identifier import will be recognized as a keyword, if 
  the compile time constant BOOST_WAVE_SUPPORT_IMPORT_KEYWORD is defined to 
  something not equal zero.
- Added new preprocessing hook functions: found_error_directive() and 
  found_warning_directive() to be called when #error/#warning directives are
  encountered. This was suggested by Andreas Sæbjørnsen.
- Added a new sample to Wave: hannibal, a partial C++ parser implementation
  initially written by Danny Havenith (http://havenith-verlinden.nl/hannibal/)
  who agreed to add this here. Thanks!
- Added new preprocessing hook function: found_line_directive() to be called 
  when a #line directive is encountered. This was suggested by Andreas
  Sæbjørnsen.
- Improved command line handling for the wave applet.
- Incorporated latest bug fixes for the Hannibal sample provided by Danny 
  Havenith. 
- Added loading of a wave.cfg file from anywhere up the filesystem hierarchy 
  starting from the main input file for the wave driver applet up to the 
  root of the file system.
- Added support_option_emit_pragma_directive to allow to control at runtime,
  whether unknown #pragma directives should be emitted or not. To maintain 
  compatibility with earlier versions this option is by default on if the
  compile time constant BOOST_WAVE_EMIT_PRAGMA_DIRECTIVES was defined to 
  be not equal to zero and it is off otherwise.
- Enabled XML serialization support.
- Added the throw_exception preprocessing hook, which gets called for every 
  occurring error (whenever an exception would have been thrown). The default
  of this new hook function is to throw the corresponding exception, which 
  reproduces the old behavior.
- Implemented a new preprocessing hook: generated_token(), which get's called
  whenever a token is about to be returned form the library. This function may
  be used to alter the token before it gets returned to the calling 
  application.
- Added a new sample 'real_positions' demonstrating the new generated_token()
  preprocessing hook and showing how to use Wave with a new token type without 
  using a new lexer type.
- Factored out the pure lex_input_interface to simplify writing different lexer 
  types for Wave.
- Added the token_statistics sample showing how to use Xpressive to build a 
  lexer for Wave.
- Changed the list_includes sample to use a lexer which is based on the lexertl 
  library written by Ben Hanson (http://www.benhanson.net/lexertl.html).
- Added a new support_option: insert_whitespace, allowing to switch off 
  whitespace insertion which is normally (by default) in place to disambiugate
  C++ tokens, which would otherwise form different tokens in the output.
- Added a new commandline option to the Wave applet: --disambiguate, allowing
  to control whitespace insertion. The default value for this option is 
  --disambiguate=1, resembling the previous behaviour. Specifying the option
  --disambiguate=0 allows to suppress whitespace insertion alltogether.
- Added pragma option values push and pop to the line, preserve and output 
  options allowing to store and restore the current option. The syntax is:
    #pragma wave options(<option>: push) and
    #pragma wave options(<option>: pop)
  where <option> may be line, preserve or output. Thanks to Eric Niebler for 
  suggesting this feature.
- Added the possibility to use static pre-compiled DFA tables for the lexertl 
  based lexer.
- Incorporated the changes from Andrei's latest version of the flex_string 
  class.
- Added the is_macro_defined(name) function to the context object as described 
  in the documentation. This function is usable with any string type compatible 
  with std::string.
- Changed behavior of the --force_include functionality, which now looks for 
  the file to be (force-)included in the current directory first.
- Switched to Re2C V0.11.2
- Added const specifiers to some of the context member functions.
- Fixed a problem in the SLex C++ lexer (cpp_tokens example).
- Fixed a runtime problem in the Re2C generated lexers when feeded with
  empty input files (thanks to Leo Davis for reporting and providing a patch).
- Added the is_eoi() function to token classes, returning true if the token
  has been initialized to be the end of input token (T_EOI) (thanks to Ovanes 
  Markarian for suggesting this).
- Added missing #includes <cstring>, <cstdlib>, and <new> to flex_string.hpp.
- Added missing #include <climits> to cpp_chlit_grammar.hpp.
- Changed found_include_directive hook function to return a bool indicating, 
  whether the file should be included (true) or skipped (false). Thanks to 
  Felipe Magno de Almeida for suggesting this feature.
- Added code to the wave driver applet ignoring a #import directive (the whole
  directive is passed through to the output) whenever the pp constant 
  BOOST_WAVE_SUPPORT_MS_EXTENSIONS is defined to something not equal to zero.
- Fixed the wave driver applet to correctly continue after a error or warning.
- Added a macro introspection facility allowing to iterate on all defined macro 
  names.
- Added a new commandline option --macronames/-m to the Wave driver application
  which lists all defined macros and their definitions to an optionally 
  specified file (default is cout).
- Fixed configuration to take into account thread related build settings.
- Added the BOOST_WAVE_SUPPORT_LONGLONG_INTEGER_LITERALS pp constant allowing
  to recognize large integer literals (larger in size than long/unsigned long) 
  even if these do not have a 'll' suffix. This pp constant is effective only, 
  if the target platform supports long long integers (BOOST_HAS_LONG_LONG is 
  defined).
- The following preprocessing hooks now return a boolean value, which when 
  returning 'true' cause the Wave library to skip the execution of the related 
  preprocessing action:
    . found_directive: allows to skip the whole directive it is called for
    . expanding_object_like_macro: allows to skip expansion of the given object
        like macro, the macro symbol is copied to the output
    . expanding_function_like_macro: allows to skip the expansion of the given
        function like macro, the whole macro invocation (including all 
        macro invocation parameters) are copied to the output without any 
        further processing.
- Changed the interpretation of the return value of the found_include_directive 
  preprocessing hook: a return value of 'false' now processes the file 
  to be included normally and a return value of 'true' now skips the processing 
  of the include file directive (the file doesn't get included). 
  This change was necessary to make the return values of the preprocessing 
  hooks consistent. Now return 'false' generally means: normal execution and 
  return 'true' generally means: skip execution of the corresponding 
  preprocessor action.
- Fixed compilation problems on gcc, fixed ambiguity with boost code (detail 
  namespace was ambigious).
- Fixed predefined macro support to be thread safe.
- Added missing file to real_positions example. Thanks to Ludovic Aubert for 
  spotting the problem.
- Unterminated C++/C comment diagnostics are now a warning and not an error 
  anymore.
  
Boost V1.34.0
- Wave Version 1.2.4
- Added the possibility to explicitly enable/disable the generation of #line 
  directives. Added a corresponding commandline argument to the Wave driver 
  tool (--line/-L) which takes either 0 or 1 as its parameter.
- Added support for #pragma wave option(command: value) directives, which 
  supports the following commands:
   . #pragma wave option(line: [0|1])  
        Enable/disable generation of #line directives
   . #pragma wave option(preserve: [0|1|2])  
        Control whitespace preservation
   . #pragma wave option(output: ["filename" | null | default])
        Redirect output to the given file (or no output, if 'null' is specified,
        or output to the file as given on the command line, if 'default' is 
        specified).
        The filename is resolved relative to the directory of the processed
        file.
  These new #pragma directives are implemented in the Wave driver tool only.
  It is possible to combine several options in one #pragma directive, i.e.
  #pragma wave option(line: 0, preserve: 2).
- Changed the signature of the may_skip_whitespace() preprocessing hook to 
  additionally take the preprocessing context as its first parameter.
- Added the possibility to the Wave tool to disable initial output by 
  specifying a '-' as the output file. This is useful for syntax checks only or
  in conjunction with the #pragma wave option(output: ...) to restrict the
  generated output.
- Improved error reporting in the Wave tool on bad output file stream state.
- Switched to Re2C V0.10.0
- Fixed some of the VC7.1 /W4 warnings.
- The Wave tool now creates the directory hierarchy of output files as needed.
- Applied some optimization, which causes skipping of the parsing for almost 
  all preprocessor directives when the if block status is false. This gains
  upto 10-20% in speed for average applications.
- Added error diagnostic for #elif without matching #if, which was missing 
  under certain circumstances.
- Avoided the evaluation of #elif expressions if one of the previous #if/#elif
  blocks of the same level was true. This gains upto another 5% of speed for
  average applications.
- The MS specific integer suffix 'i64' is now correctly supported by the Re2C
  and SLex lexer components (only when BOOST_WAVE_SUPPORT_MS_EXTENSIONS is 
  defined during compilation).
- Changed the Wave tool to print the column number of an error/warning along
  with the line number. The new format is: 'filename:line:column: error text'.
- It is now possible to recover from the unbalanced #if/#endif statement 
  warning in a proper way.
- The Wave library now automaticaly recognizes include guards in headers files
  and uses this information to avoid opening these header files more than once.
  This speeds up things by upto 10-20% depending on the concrete include files.
- Fixed the failing test t_6_023.cpp. Error reporting for illformed #else 
  directives was broken (because of some recent changes).
- Fixed the failing test t_5_007.cpp. This was caused by the automatic include 
  guard detection, which prevented the second inclusion of the specified
  include file the test was relying on.
- Added the possibility to switch off the automatic include guard detection.
- Added a new command line option to the Wave tool: --noguard/-G, which
  disables the automatic include guard detection.
- Now a header with include guards will be included correctly for a second time
  after its include guard symbol gets undefined.
- Added the generating platform to Wave's full version string.
- Made the Wave tool fully interactive when started with input from stdin and
  and output to stdout. In this mode the Wave tool preprocesses the input 
  line by line and not only after receiving the full input as normally.
- Added serialization support for the wave::context object, which stores 
  all information about defined macros and all #pragma once header information.
- Added the command line option --state (-s) to the Wave tool, which tries to 
  load the serialized information from the file given as the argument to 
  --state and save the state information at the end to the same file. 
  This option is available in interactive mode only. 
- Added possibility to verify the compatibility of the configuration used 
  during compilation of the Wave library with the config info used for the 
  application. Added a corresponding test to the Wave tool.
- Added a new predefined macro __WAVE_CONFIG__ which expands to an integer
  literal containg the configuration information the library was compiled
  with.
- Added proper versioning support to the serialization of state.
- Fixed the macro tracing information to contain the column numbers of the macro
  definitions as well (the format used is the same as for error messages).
- Fixed a memory leak in the flex_string copy on write code (thanks to Tobias 
  Schwinger for reporting this bug).
- Fixed a memory corruption bug in the Re2C scanner buffer management code
  (thanks to Andreas Sæbjørnsen for spotting the bug).
- Fixed a major performance bottleneck in the lex_token class. This speeds up 
  Wave for upto another 20-40% depending on the amount of macro expansions to 
  perform.
- Added the BOOST_SPIRIT_USE_BOOST_ALLOCATOR_FOR_TREES and the
  BOOST_SPIRIT_USE_LIST_FOR_TREES Spirit configration constants to the 
  wave_config.hpp to allow to fine tune the generated Spirit tree code. VC7.1
  gives best results when both are defined.
- Fixed a memory corruption bug triggered by a possible dangling reference.
- Fixed Wave tools startup crash when compiled with VC8.
- Added the name of the generating compiler (BOOST_COMPILER) to the full 
  Wave version info.
- Fixed all Jamfile.v2 to correctly disable RTTI for VC7.1.
- Added #pragma message("...") to be optionally supported by the Wave library.
  This may be enabled by defining the BOOST_WAVE_SUPPORT_PRAGMA_MESSAGE pp
  constant to some value different from zero.
- Fixed a couple of typos in the file cpp.cpp preventing it to compile on 
  gcc 4.1.0 (thanks to Richard Guenther for reporting these).
- Richard Guenther fixed another buffer overrun problem in the Re2C scanner.
- Fixed Jamfile.v2 files for all sample applications.
- Fixed a bug which lead to reporting of an illegal preprocessing directive
  inside not-evaluated conditional blocks under certain circumstances (thanks
  to Tobias Schwinger for reporting).
- Fixed '#define true ...', '#define false ...' and other constructs, i.e. the 
  usage of the boolean keywords as identifiers during the preprocessing. Added
  a corresponding test case (t_9_017.cpp). Thanks to Andreas Sæbjørnsen for
  reporting.
- Corrected the Jamfile[.v2] of the waveidl sample to refer to correct file 
  names (thanks to Juergen Hunold for submitting a patch).
- Fixed a bug which prevented the main iterator from returning a T_EOF token 
  at the overall end of the input. 
- Fixed a problem, where non-evaluated #elif directives never got passed to the 
  skippen_token() pp hook (thanks to Andreas Sæbjørnsen for reporting).
- Fixed a problem in the get_tokenname() function.
- Added a missing #define BOOST_WAVE_SOURCE 1 to the wave_config_constant.cpp
  file.
- Fixed exception specifications to catch all exceptions by const&.
- Fixed predefined macros to appear to be defined at a position referring to 
  a file named "<built-in>". Thanks to Andreas Sæbjørnsen for reporting.
- Fixed the Re2C lexer not to segfault on empty files anymore.
- Stripped leading and trailing whitespace for all lines in a config file (Wave
  driver tool).
- Fixed RTTI build issue for VC7.1/bjam --v2 (thanks to Rene Rivera for 
  submitting a patch for the Wave Jamfile.v2).
- Fixed certain problems reported by the Boost inspection tool.
- Fixed a couple of SunPro5.8 warnings.
- Fixed a bug resulting in a crash if a macro was redefined with a shorter
  expansion list as it was defined initially. Added a corresponding test case.
- Fixed a bug causing an infinite loop when there was a missing endif in the 
  main preprocessed file.
- Improved error recovery for illegal preprocessing directive errors.
- Improved error handling and error recovery for conditional expressions 
  (#if/#elif expressions).
- Wave now passes 160 out of 161 tests from the MCPP V2.6.1 validation 
  testsuite!
- Added new warning for invalid #line number and filename arguments
- Improved error diagnostics for invalid #line directives containing arbitrary
  tokens after at the end of the line.
- Improved error handling wrt the misuse of the __VA_ARG__ token in macro 
  definitions.
- The warning, that a file is not terminated by a newline is now issued for all
  files, not only for the main file (as previous).
- Added a couple of new test cases to verify various diagnostics.
- Fixed wave applet not to report missing #endif's when in interactive mode.
- Cleaned up the Re2C lexer code.
- Fixed a bug, where a empty line followed by an arbitrary token and followed 
  by a preprocessing directive interpreted the preprcessing directive as if it
  were the first non-whitespace token on the line. This error occured only
  if the #line directive generation was suppressed. Thanks to Joan Grant for
  reporting this problem.
- Fixed a problem in the Wave applet which prevented the correct recognition of 
  Windows file paths in a configuration file, if this path was enclosed in 
  quotes.
- Extended the copyright notice to include the year 2007.
- Fixed a problem in preserve=1 mode, when a C style comment triggered the 
  generation of a #line directive.
- Worked around a linker issue for the True64/CXX compiler, complaining about
  multiple defined symbols when using the flex_string class.
- Added missing documentation for the context::get_macro_definition function.

Sat Feb 18 2005
- Version 1.2.3
- Added a missing throw() specification to the function 
  cpp_exception::get_related_name().
- Fix Boost bug ([ boost-Bugs-1395857 ] wave redefines BSIZE).
- Added missing calls to the skipped_token() preprocessing hook which wasn't
  called for pp directives inside disabled #if blocks.
- Made the context<> type noncopyable.
- Introduced the --extended/-x command line option to the wave driver 
  executable, which enables the #pragma wave system() directive. This directive
  is now disabled by default because it may cause a potential security threat.
- Changed the what() function of the macro_handling_exception class, which now
  correctly returns the name of the exception type itself.
- Added a diagnostic message to the wave driver executable, which is issued 
  whenever a #pragma wave system() directive is found, but the -x (--extended) 
  command line argument was not given.
- Fixed long integer suffix to be allowed to be mixed case (1Ll or 2lL).
- Fixed the BOOST_PP_CAT(1e, -1) pp-token bug. Wave now correctly recognizes
  pp-number tokens, which are converted to C++ tokens right before they are 
  returned from the library.
- Moved the implementation of the token_id query functions (get_token_name(), 
  get_token_value()) to a separate source file.
- Fixed a bug, which prevented to prefer pp-numbers in files preprocessed as
  a result of #include directives.
- Fixed a bug, which prevented to open #include'd files specified by an 
  absolute path.
- Fixed a problem in the expression parser value type.
- Fixed a dynaload compilation problem with VC7.1 of the re2c lexer tests.

Sat Dec 24 13:33:53 CST 2005
- Version 1.2.2
- Added three new preprocessing hooks: 'found_directive', 'skipped_token' and 
  'evaluated_conditional_expression' (thanks to Andreas Sæbjørnsen for the 
  suggestions).
- Removed hook forwarding functions in the context_type.
- Added missing include_next case branches for get_directivename() function.
- Added new sample: advanced_hooks.
- Fixed a possible buffer overflow in the cpplexer and cpp exception classes.
- Made the cpp_grammar thread safe.
- Removed the need for the get_directivename() function. Fixed typos in the 
  predefined token table.
- Removed assertions from get_token_name() and get_token_value() and replaced 
  these with more meaningful code.
- Added the BOOST_WAVE_USE_STRICT_LEXER configuration constant which allows to
  decide, whether the '$' character will be recognized as a part of identifiers
  or not (the default is BOOST_WAVE_USE_STRICT_LEXER == 0, i.e. '$' will be
  recognized as part of identifiers).
- Added the possibility to testwave to extract a tagged comment based on a
  preprocessor constant (testwave V0.4.0).
- Made the predefined_macros_grammar thread safe.
- Added dll support for the generated Wave libraries.
- Added the const_iterator based exlicit instantiations for the Re2C lexer to 
  the built Wave library and dll.
- Added the whitespace handling policy to the context object. This actually is 
  no separate policy, it's a new preprocessing hook allowing to decide, whether
  a concrete token has to be skipped.
- Changed the --preserve option of the wave tool to take a single integer 
  argument (0: no whitespace is preserved, 1: only comments are preserved, 
  2: all whitespace is preserved)
- Edited the command line option descriptions of the wave driver.
- Fixed broken tags in documentation (magically inserted by DreamWeaver).
- Merged the new whitespace_handling policy with the existing preprocessing 
  hooks. The name of the new preprocessing hook ist may_skip_whitespace().
- Fixed compatibility issues for CW9.4 in the Wave test aplication.
- Added get_errorcode() member to the wave exception classes allowing to 
  get back the reason for the exception.
- Added boost::wave::is_recoverable(cpp_exception const&) alowing to decide,
  whether it is possible to continue after a cpp_exception has been thrown.
  This is a temporary hack to overcome the current limitation of the library
  not allowing to do generic error recovery. It allows to recover from 75% of
  the generated errors types.
- The --timer command line option for the Wave driver now prints the elapsed 
  time correctly even if a preprcessing error occured.
- Fixed an error recovery problem which skipped one token after continuing in
  case this was a pp directive.
- Added the --autooutput (-E) option to the Wave driver applet which redirects 
  the generated output to a file named after the input file changing the file 
  extension to '.i'.
- Changed all throw's to boost::throw_exception.
- Added the possibility to configure the command keyword for the wave specific 
  #pragma directives. It is now possible to define a string literal via
  BOOST_WAVE_PRAGMA_COMMAND, which will be recognized and all corresponding
  #pragma's are dispatched to the interpret_pragma() preprocessing hook.
  The default value for BOOST_WAVE_PRAGMA_COMMAND is "wave", just to ensure 
  complete backward compatibility.
- Added missing #pragma warning(pop) directives.
- Fixed a bug wrt error propagation in the expression parser.
- Fixed an assertion fired when cpp_token is used to process the quick_start 
  sample.
- Fixed a (Windows specific) bug which triggered a boost::file_system exception
  under certain conditions.
- Switched to Re2C V0.9.11
- Fixed a problem with the new '-E' (--autooutput) option.
- Added better error reporting for duplicate macro definitions to the Wave 
  tool. Added the macro_handling_exception type containing the corresponding 
  macro name via the new (virtual) get_related_name() function.
- Added the get_severity() function to the exceptions thrown by the Wave
  library.
- Extended the copyright notice to include the year 2006.
  
Mon Dec  5 22:05:22 CST 2005
Boost V1.33.1
- Version 1.2.1
- Fixed bug reported as Sourceforge bug 1274584.
- Switched to Re2C V0.9.9.
- Fixed a bug where the 'parameters' and 'definition' parameters to the 
  defined_macro callback of the preprocessing hooks were always empty (thanks
  to Stefan Seefeld for reporting).
- Fixed missing namespace specifiers in token definition macros (thanks to 
  Jozsef Mihalicza for reporting).
- Enabled --preserved and --long_long modes by default for the cpp_tokens 
  sample.
- Newline tokens reported a wrong line number (offset by one) when using the
  Re2C generated lexer (thanks to Jozsef Mihalicza for pointing this out).
- Changed file positions to carry 'unsigned int' line and column numbers.
- Fixed tokens of a generated #line directive to carry the correct column 
  numbers.
- Tokens now contain the correct filename, line and column numbers even if
  a #line directive was encountered.
- Fixed wrong line numbering in reference comments of the tests t_5_002.cpp and 
  t_5_035.cpp.
- Made sure, that preprocessor expression errors get ignored for 'passive' 
  #elif branches.
- Fixed an issue reported by the gcc debug stl.
- Added the <vc-7_1-stlport><*><rtti>off directive to all of the V1 Jamfiles.

Wed Aug 17 20:21:00 CST 2005
Boost V1.33.0
Version 1.2
- Fixed name clash wrt T_DIVIDE on FreeBSD.
- Fixed documentation of the different language_support flags.
- The support for long long suffixes is no longer bound to the variadics mode,
  it has to be enabled by the new long_long mode (default in C99).
- Fixed compilation if BOOST_WAVE_DUMP_PARSE_TREE is defined.
- Fixed lexer error message wrt long_long mode.
- Stefan Seefeld fixed a bug in the lexer, where include_next was assumed for
  included files containg a "include_" in their name.
- Fixed some trigraph token id's in the lexers.
- Added column information to the re2c generated lexer.
- Added tests for the different lexers.
- Fixed the found_include_directive preprocessing hook to carry the information
  about #include_next directives as well.
- Separated the different lexer tests.
- Fixed a bug in the whitespace eater.
- Fixed a bug where Wave emitted the found C++ comments in --preserve mode even
  if these were found inside of disabled #if/#endif blocks.
- Removed the function local static grammars to avoid possible raise conditions
  and to make CW8.3 happy.
- Unified lexer interface, adjusted namespaces.
- Added lexer testcases to the regression tests.
- Fixed test cases to scale to 64 bit platforms.
- Disabled the MS specific extensions in the lexer tests in a platform related
  way.
- Added special handling of the eof tokens inside the lexer iterator classes
  for Comeau.
- Applied a workaround proposed by David Abrahams to make the slex lexer work 
  on the CodeWarrior platforms.
  
Sun May  8 17:22:59 WEDT 2005
Version 1.1.17
- Added ill_formed_character_literal and ill_formed_integer_literal errors.
- Improved error handling and diagnostics for integer overflow in #if/#elif
  expressions.
- Fixed a bug in the testwave application which prevented the correct 
  recognition of expected errors under certain circumstances.
- Fixed a portability problem (for gcc 3.3.x) in the testwave application.
- Enforced that #if/#endif are balanced file wise.
- Changed the command line arguments for the Wave testrun to use absolute 
  directories.
- Changed the test application to return a value != zero if one of the given 
  config files were not found.
- Fixed a command line parsing problem caused by a change in the parameter
  handling inside in the program_options library.
- Switched to the most recent version of re2c (V0.9.7.dev).
- Fixed a como compilation error and several como --a warnings.
- The T_EOF token doesn't carry the value of the previous token anymore.
- Added operator==() to the token classes to fix the ambiguity error reported
  by the True64 compiler.
- Improved the error message, when empty arguments are used in pure C++ mode.
- Added character literal out of range testing and an additional corresponding 
  error message.
- Fixed parsing of long character literals (such as '\x1234').
- Fixed almost all problems diagnosed by the Boost inspection report.
- Several fixes to make the True64 compiler happy.
- Added the long long suffix handling to the C99 mode (LL/ll).
- Fixed a bug in the slex regex specifications.

Thu Apr  7 10:07:45 WEDT 2005
Version 1.1.16
- Fixed a bug in the white space eating component, which prevented a C++ 
  comment to be suppressed if it followed after another whitespace.
- Fixed the inconsistencies between the documentation and the behaviour wrt the 
  different include search paths. See the Wave driver docs for details of how
  the '-I', '-I-', and '-S' options work.
- Allowed to specify more than one config file ('@' syntax) on the command line
  of the wave driver executable.
- Changed copyrights in all files to reflect the acceptance of Wave into Boost.
- Unknown preprocessing directives were not recognised as such anymore.
- If comments shouldn't be preserved all C++ comments are replaced by newline
  tokens (instead of beeing igored completely).
- Fixed a bug in the white space eater component.
- Fixed a bug which reported wrong line numbers for error encountered during 
  retokenisation (concatination).
- Fixed a bug in the unescaping code.
- Fixed a compilation error of the testwave executable (added a missing 
  namespace specifier).
- Added a missing header to make cpp.re.cpp compile on CW.
- The predefined macro __BASE_FILE__ now returns a properly escaped file name 
  string.
- Fixed the function boost::wave::util::impl::unescape_lit().
- Added the Wave unit test framework. For now it contains about 60 unit tests
  executed by a special test driver (testwave).
- Added the '$F' replacement string to the testwave application. This allows
  to handle file paths sensitive comparison of the expected and real results.
- Fixed a minor problem in the whitespace eating component.
- Added optional trigraph conversion.
- Changed all size_t, time_t etc. to std::size_t, std::time_t etc (for CW).
- If the comments should not be preserved every C comment containing at minimum 
  one newline is now converted to a newline token.
- Added the lexed_tokens sample.
- Fixed warnings and errors reported by the CodeWarrior compiler.
- Added the '$V' replacement string to the testwave application. It expands to 
  the current BOOST_LIB_VERSION.
- Diagnosed the attempt to redefine the alternative operators as and, or etc.
- Improved error handling.
- Disabled the flex_string class for VC7, enabled to fallback to std::string 
  for this compiler.
- Renamed files to comply with the Boost rules.
- Added the first part of the MCPP validation suite to the Wave unit tests.
- Added even more missing "using namespace std;" statements for functions from
  the C runtime library. The Wave test suite now contains more than 100 unit
  tests.
- Added the $P/$P(basename) replacement string to the testwave application 
  which expands to the full path of the current file ($P) or to the current 
  directory/basename ($P(basename)).
- Fixed a bunch of portability problmes revealed by the regression tests on
  different platforms. Thanks to Stefan Slapeda for his support to make it work
  on the cw-9_4 toolset (win32).
  
Tue Mar 22 14:52:45 WEST 2005
Version 1.1.15
- Fixed a bug where the complete set of C99 predefined macros were pre-defined
  when in C++ mode and variadics were enabled.
- When in variadics or C99 mode the __BASE_FILE__ predefined macro expanded to
  <Unknown>.
- Added the --listincludes option to the Wave driver executable which allows to
  log the file names of the include files opened.
- Fixed a gcc warning in token_cache.hpp (unused variable end).
- Changed the logic behind #include_next. It now starts searching with the 
  next directory after the directory the current file (the file containing the 
  #include_next directive) is located in.
- Changed the signature of the undefined_macro preprocessing hook to take the 
  token itself and not the macro name only. This is important to pass the full
  context information about the position of the #undef directive to the 
  user provided hook (thanks to Stefan Seefeld for pointing that out).
- Fixed several broken links in the Context Policy topic.
- Fixed a bug in the handling of the #include_next directive inside of 
  non-evaluated #if blocks.
- Fixed a bug in the #include_next handling code (thanks to Stefan Seefeld).
- Changed the signature of the opened_include_file() preprocessing hook which 
  now receives not only the absolute file name of the openend include file but
  additionally gets passed the (possibly) relative path of the openend include
  file. This concrete format of the relative path depends on the format of the
  include search directory given to the library.
- Added a new preprocessing hook 'found_include_directive()' which gets called
  for every #include directive (even for those where the file to include 
  doesn't exist) and which gets passed the (expanded) token sequence found 
  after the #include directive token.
- The file names passed to the preprocessing hooks are now normalised.
- Changed the opened_include_file() preprocessing hook to receive the correct
  relative path even if the included file was found in the current directory.
- Fixed a bug which reported 'defined(or)' as invalid (similarly all the other
  alternative bit operation token types).
- Fixed a bug which prevented to define variadic macros from the command line.
- Added a 'preserve comments' mode to preserve the comments in the input stream
  not inserted into macro definitions.
- Added a new --preserve (-p) command line switch to the wave driver 
  application to allow comments to be preserved in the generated output stream.
  
Mon Feb 21 09:30:04 WEST 2005
Version 1.1.14 (Fixes in response to the Boost review)

Wave was accepted into Boost! 

With special thanks to Tom Brinkman, who volunteered to be the review manager.

With thanks to David Abrahams, Beman Dewes, Reece Dunn, Larry Evans, 
Doug Gregor, Joel de Guzman, Baptiste Lepilleur, Andy Little, Paul Mensonides, 
Dan Nuffer, Andreas Pokorny, Vladimir Prus, Gennadiy Rozental, Michiel Salters, 
Jonathan Turkanis, Chris Uzdavinis, Pavel Vozenilek, Michael Walter for bug 
reports, fixes and hints.

- Added support for the MS extensions #region and #endregion, which simply get
  ignored by Wave. The support for these is enabled only, when the pp constant
  BOOST_WAVE_SUPPORT_MS_EXTENSIONS is defined. Otherwise these get flagged as 
  an illegal preprocessor directive (as before).
- Fixed a problem, where the replacement text for a #pragma directive got lost
  if this directive was on the last line of a processed (include-)file.
- Changed the default value for BOOST_WAVE_SUPPORT_MS_EXTENSIONS for non-
  Windows systems to zero.
- Updated outdated external links in the documentation.
- Fixed certain grammatical and stylistic quirks in the documentation.
- Fixed a problem in libs/wave/build/Jamfile.v2 (as reported by Larry Evans).
  Fixed the Jamfile.v2 in the samples directories accordingly.
- Added the '<toolset>vc-7_1:<rtti>off' to all Jamfile.v2 files to adjust for 
  the internal buffer overflow bug in the VC7.1 compiler (reported by Joel de 
  Guzman).
- Changed the '<toolset>vc-7_1:<rtti>off' to '<toolset>vc-7.1:<rtti>off' as
  required by the Boost.Build.v2 library (suggested by Vladimir Prus).
- Finally fixed the Jamfile.v2 file (after a suggestion from Reece Dunn)
- Fixed the column number reported for tokens for Slex lexer based 
  configurations (reported by Baptiste Lepilleur).
- Added the __BASE_FILE__ predefined macro, which contains a string literal 
  of the main file name to preprocess (the one the context<> template was
  created with). (suggested by Pavel Vozenilek)
- Used the boost::reverse_iterator instead of the std::reverse_iterator
  for the flex_string class to allow compilation of Wave with VC7.0
  (as suggested by Reece Dunn).
- Fixed a problem in the include_path template, which throwed a 
  boost::filesystem exception whenever a character was used in a file name
  to include, which is marked as illegal by the default name checker of the
  boost::filesystem::path.
  
Version 1.1.13 (Boost review candidate 2, bug fixed version)
- Fixed a problem, where the context<> template referenced temporary iterator
  objects from the underlying stream (thanks to Michiel Salters for reporting
  this).
- Fixed a bug in the re2c lexer, which allowed to dereference the end iterator 
  of the underlying input stream (thanks to Doug Gregor for pointing this out).
- Fixed several assertions fired by the iterator checking code of the VC8 stl.

Version 1.1.12 (Boost review candidate)
- A rough performance analysis showed, that 30% of the time is spent parsing 
  the input for pp directives (cpp_grammar), 35% of the time is spent inside
  the flex_string code, mainly in the copy constructor and assignment 
  operator, 15% of the time is spent inside the list and vector member 
  functions, 10% is spent for memory allocation but only 1% of the time is 
  spent in the re2c lexer.
- Identified a performance problem, where the token_cache was instantiated
  for every created lexer object, but needed to be initialised only once.
- Added #include <wave_version.hpp> to wave_config.hpp
- Fixed problems reported by the gcc 3.4.1 compiler.
- Adjusted Jamfiles for the new toolset names introduced in Boost V1.32.

Version 1.1.11
- Updated copyrights.
- Fixed some bugs introduced by the latest refactoring.
- Tried to fix the expansion of macros, which replacement-list terminates in a 
  partial macro expansion. No success so far.

Version 1.1.10
- Refactored some of the macro map (macro namespace) code (added comments, 
  splitted into separate files),
- Fixed some typename errors in cpp_macromap.hpp (thanks to Vladimir Prus).
- Fixed the BoostBuild V2 Jamfiles (thanks to Vladimir Prus).

Version 1.1.9
- Moved all of the #pragma wave option(value) operators out of the wavelib into 
  the wave driver program. Removed enable_trace() and trace_flags() policy
  functions. Renamed trace_policy into context_policy.
- Added the defined_macro() and undefined_macro() preprocessing hooks to allow
  easily to build macro cross referencers and such.

Version 1.1.8
- Replaced the usage of the string::erase() and string::insert() functions, 
  which were the only non-const string member functions used.
- Token pasting is now well defined in variadics mode (was in C++0x mode only).
- Changed the timing code in the wave driver to include the parsing of 
  files included by the --forceinclude command line switch.
- Performance measurements (very informal) [sec], the files are some of the
  preprocessor specific test cases from Paul Mensonides chaos_pp library.

                        std::string   flex_string   const_string   const_string
                                                      12 Byte        28 Byte
    arithmetic.cpp        2.543          1.742         0.951           1.001
    array.cpp             2.453          1.762         0.951           1.011
    comparison.cpp        0.560          0.340         0.270           0.280
    control.cpp           0.590          0.340         0.290           0.300
    debug.cpp             0.370          0.310         0.190           0.190
    detection.cpp         0.050          0.060         0.030           0.030
    extended.cpp          0.370          0.260         0.190           0.190
    facilities.cpp        0.610          0.340         0.290           0.300
    iteration.cpp         1.081          0.550         0.410           0.450
    list.cpp              1.742          1.141         0.811           0.851
    logical.cpp           0.070          0.200         0.040           0.040
    punctuation.cpp       0.030          0.080         0.020           0.020
    repetition.cpp        1.392          0.851         0.650           0.690
    selection.cpp         0.440          0.270         0.210           0.220
    slot.cpp              0.680          0.350         0.240           0.270
    tuple.cpp             0.420          0.240         0.190           0.210
                      

Wed Aug 25 13:23:27 WEDT 2004
Version 1.1.7
- Branched for Boost Release.
- Removed several features from the code base:
  . removed C++0x support
  . removed TST support
- Fixed the program_option validator syntax, which has changed since the last 
  update.
- Removed misleading configuration options from the cpp_config.hpp file, 
  because the application will have to use the same config options as were used
  during the compilation of the library.
- Changed the naming convention of typedef'd types in the library. Removed the 
  _t suffix, wherever possible.
- Updated the documentation to reflect the removal of the C++0x features.

- Changed the licensing scheme to:
// Copyright 2004 Joe Coder. Distributed under the Boost
// Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

Mon May 24 10:02:47 WEDT 2004
Version 1.1.6
- Fixed a incompatibility with the new program_options version.

Version 1.1.5
Version 1.0.6
- Fixed a bug, which reported an #include statement as ill formed, if it was 
  followed by an empty C comment only. This was an error in the cpp.re regular 
  expression for C comments. Additionally, since this change simplified the 
  Re2C generated lexer a lot it was possible to remove the compiler workaround 
  for the VC7.1 compiler which prevented the optimization of this lexer.
  
Mon Mar 29 09:36:59 WEDT 2004
- Corrected the signature of the main() functions (was main(int, char const*[])).

Sun Mar 28 12:55:59 WEDT 2004
Version 1.1.4
- Fixed a problem, where the first returned token was lost, whenever a 
  --forceinclude file was given.
- Adjusted the Wave driver and the other samples to use the new program_options 
  library syntax (V1.1.x only).
  
Mon Mar  1 19:14:21 WEST 2004
Version 1.1.2
Version 1.0.4
- Fixed a problem, which does not report an error, if in a #define statement in 
  between a macro name and its replacement list were no whitespace given.
- Fixed a bug, which generated an unexpected exception of the $ character in the 
  input.
- Macro definitions, which differ by whitespace only (one definition contains 
  whitespace at a certain position, the other definition does not) are correctly 
  reported as a warning now.
- Fixed a problem, where different formal argument names during macro 
  redefinition were not flagged as a warning.
- A wide character string used in a #line directive wasn't flagged as an error. 
  
Sun Feb 29 19:10:14 WEST 2004
Used the test suite distributed with the mcpp V2.4 preprocessor to fix a bunch
of mostly minor issues:
- Fixed trigraph backslash followed by a newline handling (??/ \n) in the 
  re2c (C/C++ and IDL) scanners.
- Fixed a digraph/trigraph token type handling problem during macro expansion.
- Fixed a digraph/trigraph token type problem during handling of the null 
  preprocessor directive.
- Fixed several signed/unsigned conversion bugs in the expression evaluator.
- Fixed the || and && operators in the expression evaluator to stop evaluation,
  as only the outcome of the overall expression is determined.
- Fixed the expression evaluation engine to detect divide by zero errors.
- Fixed a bug with operator || and && arithmetic (the deduced type was wrong).
- Fixed a bug with the unary operators ! and - which IN conjunction with an 
  arithmetic operation yielded A wrong result type.
- Fixed a bug, which reported a macro definition as an invalid redefinition, if
  it was different from the original definition only by different whitespaces.
- Fixed a bug, which reported the redefinition of one of the alternative tokens
  as 'and', 'bit_and' etc. as invalid.
- Fixed a bug in the character literal parser, which prevented the recognition
  of multibyte character literals.

- Moved the cpp_token_ids.hpp header into the main wave.hpp header, because the
  values defined therein aren't changeable by the user anyway.
- Fixed some spelling errors in the documentation (thanks to Rob Stewart).

Tue Feb  3 20:20:16 WEST 2004
- Fixed the problem, that macro definitions in a config file were flagged as 
  an error, if there was any whitespace in between the -D and the macro name
  (same problem existed for -P).
  
Fri Jan 30 20:28:27 WEST 2004
- Fixed a missing boostification in the trace support header.
- Added a missing std:: namespace qualification to the list_includes.cpp sample 
  file.
- Fixed line ending problems with the cpp.re and idl.re files.
- Added quick_start sample.

Sun Jan 25 20:26:45 WEST 2004
This version was submitted to Boost as the review candidate (V1.1.0)
- Fixed invalid explicit instantiation syntax as reported by the Comeau 
  compiler.
- Added a missing header to flex_string.hpp.

Sat Jan 24 19:47:44 WEST 2004
- Completely decoupled the used lexer from the preprocessor.
- Unfortunately had to change the template interface of the context class. It 
  now instead of the token type takes the type of the lexer to use.
- Reintroduced the cpp_tokens, list_includes and waveidl samples. 
  . cpp_tokens is based on the SLex lexer
  . list_includes shows the usage of the include file tracing capability
  . waveidl uses the Re2C based IDL lexer in conjunction with the default token
    type
  
Tue Jan 13 20:43:04 WEST 2004
- Fixed several compilation issues under linux (gcc 3.2.3, gcc 3.3, gcc 3.3.2, 
  gcc 3.4, Intel V7.1)
- Fixed a compatibility problem with Spirit versions older than V1.7.

Mon Jan 12 20:39:50 WEST 2004
- Boostified the code base:
  . Moved code into namespace boost.
  . Prefixed all pp constants with "BOOST_".
  . Refactured the directory structure.
- Removed IDL mode and SLex lexer from the code base. These will be re-added as 
  samples.
- Changed the Wave configuration system to be more flexible (all 
     #if defined(BOOST_WAVE_...) changed to #if BOOST_WAVE_... != 0),
  which allows to configure the library without changing the code base itself
  
Sat Jan 10 18:17:50 WEST 2004
- Incorporated Andrei Alexandrescu's latest changes to the flex_string class, 
  which resulted in an overall spedd gain of about 5-10%.
  
Wed Jan  7 17:46:45 WEST 2004
- Found a major performance hole! The achieved general speedup is about 50-70%.
- Added missing old MS specific extensions to the re2c lexer (_based, 
  _declspec, _cdecl, _fastcall, _stdcall, _inline and _asm).
- Added support for #include_next (as implemented by gcc).
- Fixed compilation problems with gcc 3.3.1
- Avoid to look up in symbol table of a potential macro name twice.
- Added the Spirit SLex lexer sample to the Wave source tree, because it was 
  removed from the Spirit distribution.
- Removed the configuration option, which allowed to reverse the names stored 
  in the symbol tables.
- Implemented experimental support for using a TST (ternary search tree) as the
  container for the symbol tables.
   
Sun Jan  5 12:30:50     2004
- Released V1.0.0

Sun Jan  4 00:11:50     2004
- Removed tabs from the flex_string.hpp file.
- Modified the input_functor.hpp file to sqeeze out some milliseconds at 
  runtime.
- The --timer option now prints the overall elapsed time even if an error 
  occured.
- Added support for #pragma once.

Fri Jan  2 22:58:54     2004
- Fixed a bug in the code, which predefines the preprocessor constants.
- Fixed a bug in intlit_grammar<> initialisation code.

Thu Jan  1 21:15:03     2004
- Fixed a bug while predefining a macro with a value through the commmand line.
- Fixed a bug, which reported a macro definition as illegal, if the redefined 
  macro was a function like macro with parameters.
- Fixed a bug, if concatenation of two tokens resulted in a C++ comment start 
  token.
  
Thu Jan  1 15:01:54     2004
- Finished license migration.

Wed Dec 31 12:23:55     2003
- Changed the copyright and licensing policiy to be Boost compatible.

Wed Dec 31 12:01:14     2003
- Fixed a problem while compiling certain headers from the Microsoft Windows 
  SDK:
        #define CreateWindowA(lpClassName, lpWindowName, dwStyle, x, y,\
        nWidth, nHeight, hWndParent, hMenu, hInstance, lpParam)\
        CreateWindowExA(0L, lpClassName, lpWindowName, dwStyle, x, y,\
        nWidth, nHeight, hWndParent, hMenu, hInstance, lpParam)
  where essentially is no whitespace between the parameter list and the macro
  replacement list.
- Fixed a problem with the MS extension __declspec, which now is recognized
  correctly.
  
Sat Dec 27 14:48:29     2003
- Fixed remaining problems with assign/assign_a.
- Fixed some gcc warnings about signed/unsigned comparision mismatch.

Tue Nov 11 20:51:41 WEST 2003
- Changed the IDL mode to recognize identifiers only. All keywords (except 
  'true' and 'false') are returned as identifiers. This allows for easy 
  extension of the IDL language. The drawback is, that after preprocessing 
  there needs to be just another lexing stage, which recognizes the keywords.
- Fixed a possible problem, when in between a #if/#elif directive and a 
  subsequent opening parenthesis Wave finds no whitespace:
    #if(_WIN_VER >= 0x0500)
  is now recognized correctly. 
  (This problem was pointed out by Porter Schermerhorn).
  
Sun Nov  9 21:05:23 WEST 2003
- Started to work on implementation of an IDL lexer for the TAO idl compiler.
  . Branched off the Re2C C++ lexer and related files as a starting point for 
    the new IDL lexer. Added connfiguration means to allow compile time
    decision, in which mode to operatoe (C++ or IDL).
  . Implemented the Re2C based IDL lexing component.
  . Fixed all occurences of non-IDL tokens (as T_COLON_COLON and T_ELLIPSIS)

Sat Nov  8 20:05:52 WEST 2003
- Version 1.0.0
- Munged the email addresses embedded within the source files.
- Adjusted for the new actor names in Spirit (assign_a and append_a).

Thu Aug 21 16:54:20     2003
- Removed the internally used macro 'countof()' to avoid possible nameclashes 
  with user code.
- Fixed a bug, which prevented the execution of the concatination operator '##'
  while expanding object-like macros.
  
Tue Aug  5 10:04:00     2003
- Fixed a false assertion, if a #pragma directive started with some whitespace 
  on the line.
- Added the #pragma wave timer() directive to allow rough timings during 
  processing. This is done on top of a new callback hook for unrecognized 
  #pragma's, which allows to easily add new pragma commands without changing 
  the Wave library.
- Fixed a bug in the whitespace insertion engine, which prevented the insertion 
  of a whitespace token in between two consecutive identifier tokens or a 
  integer literal token followed by an identifier token.
- Fixed a bug during macro concatenation, which allowed to concatenate 
  unrelated tokens from the input stream:
    #define CAT(a, b) PRIMITIVE_CAT(a, b)
    #define PRIMITIVE_CAT(a, b) a ## b
    #define X() B
    #define ABC 1
    CAT(A, X() C) // AB C
    CAT(A, X()C)  // correct: AB C, was 1
- Fixed a 64 bit portability problem.
- Added pragma wave timer(suspend) and wave timer(resume)
- Fixed a ODR problem with static initialization data for predefined macros.
- Ported the iterators to the new iterator_adaptors.
- Updated the documentation to reflect the recent changes

Sun Jun 29 12:35:00     2003
- Fixed 64 bit compatibility warnings.
- Fixed a bug, which prevented the correct recognition of a #line directive, if
  only the filename part of this directive was generated by a macro expansion.
- Fixed a bug during macro expansion of conditional expressions, which 
  prevented the correct expansion of certain scoped macros.
  
Fri Jun 27 09:50:14     2003
- Changed the output of the overall elapsed time (option --timer) to cerr.
- Added a configuration constant WAVE_REVERSE_MACRONAMES_FOR_SYMBOLTABLE, which
  reverses the macro names while storing them into the symbol table, which 
  allows to speed up name lookup especially, if the macro names are very long
  and if these share a common prefix.
- Fixed a very subtle bug, which prevented the recognition of fully qualified
  macro names during the macro expansion of conditionals expressions (for 
  #if/#elif).
- Improved the error output for the illformed pp expression error.
  
Thu Jun 26 08:20:30     2003
- Done a complete spell check of the source code comments.

Wed Jun 25 20:33:52     2003
- Changed the conditional expression engine to work with integer numeric 
  literals only. Distinguished signed and unsigned literals.
- Importing a region twice is allowed now.
- Fixed a bug, which does not removed all placeholder tokens from a expanded 
  token sequence while evaluating conditional expressions (C++0x mode only).

Wed Jun 25 15:01:51     2003
- Changed the conditional expression engine to respect the type of numeric 
  literals, now expressions like '#if 1 / 10 == 0' evaluate correctly (to true
  :-)
- Fixed a bug, where macro names referring to global macros (as ::A::B) were 
  not correctly recognized under certain circumstances.
- Empty parameter lists for macros with ellipses only sometimes generated a 
  placemarker token in the output:
    #define STR(...) #__VA_ARGS__
    STR()   // resulted in "§" instead of "" .

Wed Jun 25 08:35:06     2003
- Fixed several gcc compilation errors (missing typename's etc.)
- Fixed a compilation problem, if Wave is built on top of the SLEX scanner.
- Reformatted the --timer output from pure seconds to a more reasonable format.

Fri Jun 20 19:33:30     2003
- Changed the enable_tracing function of the tracing_policies to take a 
  trace_flags variable instead of a bool, to allow to control tracing with more
  granulation.
- Added the tracing_enabled function to the tracing_policies, which returns the 
  current tracing status.
- Updated the documentation of the tracing policies.

Thu Jun 19 21:45:39     2003
- Reactivated the list_includes sample with the help of the new include file 
  tracing facility.

Thu Jun 19 17:55:35     2003
- Eliminated the TraceT template parameter from the macromap<> template.
- Added two hooks to the trace policy to allow to trace the opening and 
  closing of include files.

Thu Jun 19 14:08:10     2003
- Added the command line option --timer, which enables the output to std::cout
  of the overall elapsed time during the preprocessing of the given file.

Fri Jun 13 09:11:29     2003
- Emitted an error message, if an ellipses was found as a formal macro 
  parameter and variadics were disabled.
- Fixed a false error message, that the last line was not terminated with a 
  newline, which occured, if no output was generated by the last line of the
  source file.
  
Thu Jun 12 15:20:22     2003
- Fixed the recent change in argument expansion for the variadics/C99/C++0x 
  mode.
- Fixed a problem, where an additional whitespace between _Pragma and the 
  opening parenthesis resulted in a false error message.
- Used a pool allocator for the token sequence containers (std::list<>'s),
  which gives a speed gain of more than 60% (while profiling the Order 
  library).
  
Wed Jun 11 22:18:54     2003
- Fixed a macro scoping/expansion problem, when a macro returned a full scope
  which is continued on the call site to form a full qualified name, the name 
  wasn't recognized correctly:
    # region A
    #  define MACRO 1
    #  region B
    #   define MACRO 2
    #  endregion
    # endregion
    # define ID(x) x
    ID(A)::MACRO     // 1
    ID(A::B)::MACRO  // 2, was expanded to A::B::MACRO
- Changed the expansion of macro arguments such, that these will be expanded 
  only, if the result is to be used for substitution during the expansion
  of the replacement list.
  
Wed Jun 11 14:40:29     2003
- Included a whitespace eating finite state machine (FSM) for minimal 
  whitespace in the generated output. This was suggested by Paul Mensonides.
- Updated the acknowledgement section

Wed Jun  4 08:03:04     2003
- Fixed a bug reported by Faisal Vali, which prevented the correct evaluation 
  of conditional expressions, if these referenced macro names, which expanded 
  to a sequence containing non-expandable tokens.
- Fixed the above bug for #elif directives too (in the first place this was 
  fixed for #if directives only)
  
Mon May 26 22:15:40     2003
- Added missing copyrights in several files.
- Fixed false output, if a unknown _Pragma were encountered.
- Fixed a macro expansion problem with qualified names, were constructs like
  the following were not expanded correctly:
    #define ID(x) x
    #region SCOPE
    #  define TEST 1
    #endregion
    ID(SCOPE::) TEST    // should expand to 1
- Changed #import semantics for macros from copy semantics to reference 
  semantics, i.e. macros are now considered to be implicitly imported into the 
  scope, where they are defined. If a macro is imported into another scope and 
  the original macro is undefined, the imported macro still exists. Further, 
  if the imported macro is expanded, then while rescanning the original macro 
  is disabled too:
    #region A
    #  define B(x) x
    #endregion
    #import A
    B    (A::B) (*) // A::B(*)
    A::B (B)    (*) // B(*)
    B    (B)    (*) // B(*)
    A::B (A::B) (*) // A::B(*)
- Fixed a recently introduced problem, where placemarker tokens slipped through 
  to the output under certain conditions (in variadics/C99/C++0x modes only).

Mon May 19 16:30:49     2003
- Fixed a bug, which prevented the recognition of the __lparen__, __rparen__ or 
  __comma__ alternative tokens, if these were the first token after an emitted
  #line directive (reported by Vesa Karvonen).
- Added an optimization, that only those tokens are considered for a macro 
  expansion, which may result in an expansion.
  
Tue May 13 18:16:26     2003
- Fixed a newly introduced problem, where a omitted argument consisting out 
  of whitespace only were failed to be replaced by a placemarker token. This 
  lead to problems with constructs like the following:
    #define paste(a, b, c) a ## b ## c
    paste(1, , 3)  // should expand to 13, but expanded to 1## 3
- Fixed a problem with the tracing support, which throwed an unexpected 
  exception if there were too few arguments given while expanding a macro.
- Allowed to open and to import the global scope ('#region ::' and 
  '#import ::').
- Fixed a bug, if more than one file was given with a --forceinclude command 
  line option.

Sat May 10 21:30:29     2003
- Added __STDC_FULL_REGION__ and __STDC_CURRENT_REGION__ to the list of not 
  undefinable macros.
- In normal C++ mode and C99 mode the #ifdef/#ifndef and the operator defined()
  should not support qualified names. This is fixed now.
- Updated the documentation.
- Fixed minor gcc -Wall compilation warnings.
- Added better error support for qualified names used as arguments for #ifdef,
  #ifndef and operator defined().
  
Sat May 10 09:51:18     2003
- Removed the feature, that the comma before the ellipsis parameter in a macro
  definition may be omitted.
- Resolved an issue with the expansion of qualified macros, when these 
  qualified names were partially generated by a previous macro expansion
- Allowed to specify fully qualified names as arguments to the #region directive
  
Wed May  7 22:44:21     2003
- Changed the names of __SCOPE__ and __FULL_SCOPE__ predefined macros to 
  __STDC_CURRENT_REGION__ and __STDC_FULL_REGION__ resp. The names are subject 
  to change if the #region keyword actually will be renamed to #scope/#module
  or whatever.
- In C++0x mode it is now possible to omit the last comma before a variadics
  ellipsis in a macro definition:
    #define cat_i(a, b, c, d, e ...) a ## b ## c ## d ## e 
- Fixed a bug in the stringize code, where an ellipsis to stringize resulted in
  stringizing of the first ellipsis parameter only. Preserved the original 
  whitespace delimiting in between the ellipsis arguments.
- Introduced the wave::language_support enum for convenient switching of the 
  supported language features throughout the library.
- Fixed a bug, which prevented the definition of the predefined macro 
  __WAVE_HAS_VARRIADICS__, if --variadics were given on the command line.
  
Tue May  6 15:49:45     2003
- Made predefined macros available at every macro scope without qualification.
- Predefined a new macro in C++0x mode: __STDC_GLOBAL__, which is defined at 
  global macro scope only and equals to '1' (integer literal).
- In C++0x mode there are two new predefined macros: 
    __SCOPE__:      expands to the last part of the qualified name of the 
                    current macro scope
    __FULL_SCOPE__: expands to the full qualified name of the current macro 
                    scope 
    
Mon May  5 23:02:48     2003
- Fixed a problem in the new well defined token pasting code, which occured for
  constructs like the following:
    #define is_empty(...) is_empty_ ## __VA_ARGS__ ## _other
  i.e. where two or more '##' operators were contained in the replacement text.
- Implemented __comma__, __lparen__ and __rparen__ alternative pp-tokens, which 
  may be used as the ',', '(' and ')' tokens during preprocessing. These are 
  only converted to there respective string representation in a special 
  translation phase after preprocessing. This was proposed by Vesa Karvonen.
- Changed the macro scoping rules to: "If a qualified name does not find a 
  nested name, it is not a qualified name to the preprocessor." This seems to 
  be the simplest usable solution for the possible ambiguities.
- Fixed a bug in the macro expansion engine in C++0x mode, where the skipping 
  of whitespace inside of a qualified name wasn't consistent.

Sun May  4 10:48:53     2003
- Fixed a bug in the expression grammar, which prevented 'not' to be recognized
  as a valid operator.
- Qualified names are now supported as parameters to #ifdef and #ifndef too.
- Remove one specialization of the macro expansion engine. It gets instantiated
  only twice now (for the main input iterator and for list<>'s  of tokens.
- Simplified the required explicit specialization of the defined_grammar
  template. It has to be explicitely instantiated by providing the token type
  only (just as for the explicit instantiations of the other grammars).

Fri May  2 22:44:27     2003
- Qualified names are now allowed as parameters to the operator defined() in 
  C++0x mode.
- Separated the defined() functionality into a separate translation unit to 
  work around a VC7.1 ICE.
  
Fri May  2 15:38:26     2003
- The C++0x mode now has a special set of predefined macros.
- The predefined macro __WAVE_HAS_VARIADICS__ is now defined in C99 and C++0x 
  modes too (--variadics is implied for these modes).
- Updated the documentation to reflect the recent changes and additions.
- In C++0x mode Wave now supports macro scopes:
    - new keywords #region/#endregion/#import
    - qualified macro names
- In C++0x mode Wave now supports token pasting of unrelated tokens. These are
  concatenated, the result is re-tokenized and inserted into the output stream.
- Fixed a minor bug in the macro expansion engine, if a qualified function-like
  macro was found in an object-like context.
- Fixed an issue with well defined token pasting of unrelated tokens.

Tue Apr 29 08:47:37     2003
- Fixed a bug in the macro expansion engine, which prevented the expansion 
  of a certain macro under specific conditions (if the left of two tokens to 
  concatenate were a disabled one (T_NONREPLACABLE_IDENTIFIER), then the 
  resulting token was disabled too).
- Added additional diagnostics to the Wave driver to disambiguate the C99 and 
  C++0x modes.
- Implemented a new API function and a corresponding Wave driver command line
  option, which allows to specify one or more include files to be preprocessed
  before the regular file is preprocessed (the files are processed as normal
  input and all the resulting output is included, before processing the regular 
  input file). The Wave driver command line option is --forceinclude (-F).
- Wave now compiles the Order library from Vesa Karvonen.
  
Mon Apr 28 07:57:10     2003
- Fixed a bug in the macro expansion engine.
- Removed a lot of (not needed) whitespace in the generated output (but still 
  not optimal).

Sat Apr 26 20:30:53     2003
- Fixed a bug in the initialization code of the Slex lexer while working in 
  C99 mode (reported by Reece Dunn).

Fri Apr 18 08:37:35     2003
- Fixed the handling of option_value's inside of pragma directives:
    _Pragma("wave option(option_value)")
  inside which all all whitespaces were deleted.
- Started to implement experimental macro scoping.

Thu Apr 10 10:20:07     2003
- Fixed a problem with the #pragma wave stop(), where only the first token 
  inside the stop directive was output, when the preprocessor stops in result
  of this pragma.
- Implemented a new #pragma wave system(command), which spawns a new operation
  system command exactly as specified inside the system directive, intercepts
  the stdout output of this process, retokenizes this output and inserts the
  generated token sequence in place of the original #pragma or operator _Pragma.
  Please note that the generated output is _not_ subject to any macro expansion
  before its insertion as the replacement of the pragma itself. If you need to 
  macro expand the replacement text, you always may force this by writing:
    #define SCAN(x) x
    SCAN(_Pragma("wave system(...)"))
  which re-scans the replacement once.
- Replaced the Wave position_iterator with the boost::spirit::position_iterator
  (without any problems!).
  
Mon Apr  7 10:45:30     2003
- Fixed macro_trace_policies::expand_object_like_macro not to be called with 
  the formal arguments as one of its parameters.
- Updated the documentation to reflect the changes needed for the tracing 
  stuff.
  
Mon Mar 31 19:07:05     2003
- Fixed variadics support in the trace output.
- Fixed preprocessing of operator _Pragma() before it's execution.
- Added _Pragma("wave stop(errmsg)") (#pragma wave stop(errmsg)) to allow 
  diagnostics output from inside macro expansion.
- Fixed operator _Pragma for unknown pragmas (these are simply put through to
  the output).
- Implemented a maximal possible include nesting depth to avoid an out of 
  memory error. The initial value for this is configurable through the compile 
  time constant WAVE_MAX_INCLUDE_LEVEL_DEPTH, which defaults to 1024, if not 
  given.
  Additionally this may be enlarged through a new command line option:
  -n/--nesting (Wave driver only).

Sun Mar 30 20:40:17     2003
- Implemented the predefined macro __INCLUDE_LEVEL__, which expands to a 
  decimal integer constant that represents the depth of nesting in include 
  files. The value of this macro is incremented on every '#include' directive 
  and decremented at every end of file. 
- Implemented the operator _Pragma(). It is recognized in C99 mode and whenever 
  variadics are enabled.
  
Sun Mar 30 08:30:12     2003
- Changed the tracing format to be more readable.
- Changed the tracing #pragma's to
    enable tracing:     #pragma wave trace(enable)
    disable tracing:    #pragma wave trace(disable)
  or
    enable tracing:     #pragma wave trace(1)
    disable tracing:    #pragma wave trace(0)
- Changed the semantics of the -t (--traceto) switch. Without any -t switch 
  there isn't generated any trace output at all, even, if the corresponding
  #pragma directives are found. To output the trace info to a file, the 
  '-t file' syntax may be used, to output to std::cerr, the '-t-' (or '-t -')
  syntax may be used.

Fri Mar 28 17:27:25     2003
- Added a new template parameter to the wave::context<> object, which allows
  to specify a policy for controlling the macro expansion tracing. The default
  macro_trace_policy does no tracing at all. This way one can add specific
  macro expansion tracing facilities to the library.
- #pragma directives starting with a STDC identifier are no longer not macro 
  expanded in C++ mode, in C++ mode these are now expanded as usual, in C99 
  mode not.
- The tracing can be enabled/disabled from inside the preprocessed stream by
  inserting a special #pragma directive:
    enable tracing:     #pragma wave_option(trace: enable)
    disable tracing:    #pragma wave_option(trace: disable)
- The Wave driver now allows to specify a destination for the macro expansion 
  tracing trough a new command line switch: '-t path' or '--traceto path'. If
  this option isn't given, the trace output goes to stderr.
- The Wave driver now allows to specify the name of the file, where the 
  preprocessed result stream is to be saved: '-o path' or '--output path'. If 
  this option is not given, the output goes to stdout.
  
Wed Mar 26 20:39:11     2003
- Fixed a problem with alternative tokens (as 'and', 'or' etc.) and trigraph
  tokens, which were not correctly recognized inside #if/#elif expressions.
- Alternative tokens ('and', 'or' etc.) are no longer subject to a possible 
  macro redefinition.
- Fixed the special handling of 'true' and 'false' during the macro expansion 
  of #if/#elif expressions.

Tue Mar 25 12:12:35     2003
- Released Wave V0.9.1

Mon Mar 24 13:34:27     2003
- Implemented placemarkers, i.e. Wave now supports empty arguments during macro 
  invocations. This must be enabled by means of a new pp constant:
  WAVE_SUPPORT_VARIADICS_PLACEMARKERS which must be defined to enable the 
  placemarker and variadics code and by defining the command line option 
  '--variadics' (Wave driver only).
- Implemented variadics, i.e. Wave now supports macros with variable parameter 
  counts. This must be enabled by means of the pp constant:
  WAVE_SUPPORT_VARIADICS_PLACEMARKERS which must be defined to enable the 
  placemarker and variadics code and by defining the command line option 
  '--variadics' (Wave driver only).
- Implemented a C99 mode. This mode enables variadics and placemarkers by 
  default and rejects some specific C++ tokens (as the alternate keywords and 
  '::', '->*', '.*'). This mode must be enabled by the means of the pp constant
  WAVE_SUPPORT_VARIADICS_PLACEMARKERS (see above). The C99 mode is enabled by 
  the command line switch '--c99' (Wave driver only).
  This involved some changes in the C99/C++ lexers.
  
Fri Mar 21 16:02:10     2003
- Fixed a bug in the macro expansion engine, which prevented the expansion of
  macros, which name was concatenated out of a identifier and a integer 
  followed directly by another identifier:
    #define X() X_ ## 0R()  // note: _zero_ followed by 'R'
    #define X_0R() ...
    X() // expanded to:  X_0R(), but should expand to ...
  This is a problem resulting from the fact, that the Standard requires the 
  preprocessor to act on so called pp-tokens, but Wave acts on C++ tokens.
  
Thu Mar 20 21:39:21     2003
- Fixed a problem with expression parsing (#if/#elif constant expressions), 
  which failed to produce an error message for expressions like
    #if 1 2 3 4 5
  i.e. where the token sequence starts with a valid constant expression, but 
  the remainder of the line contained other tokens than whitespace.
- Integrated the flex_string class from Andrei Alexandrescu (published on the
  CUJ site) to get COW-string behaviour for the token values and position 
  filename strings. This resulted in a major overall speedup (about 2-3 times 
  faster in dependency of the complexity of pp usage in the input stream).
- Fixed a bug, which reported ill formed #if/#else expressions as errors, even 
  if the current if block status (conditional compilation status) is false.
- Added a warning, if the last line of a file does not end with a newline.
- Improved error recognition and handling for malformed preprocessor directives

Mon Mar 17 19:53:29     2003
- Fixed a concatenation problem: constructs like a##b##c where expanded 
  incorrectly.
- Optimized the recognition of pp directives: 
    - the parser is used only, if the next non-whitespace token starts a pp 
      directive 
    - null directives now are recognized without calling the parser
    - the parser isn't called anymore, if the if_block_status is false and no
      conditional pp directive (#if etc.) is to be recognized.
  These optimizations give a speed improvement by upto 40%.
- Removed adjacent whitespace during macro expansion (needs to be revised, 
  since there is some whitespace left, which may be removed)
    
Sun Mar 16 23:19:11     2003
- Fixed a problem with include paths given on the command line, if the file
  to preprocess was not given as a full path (driver executable).
- Fixed a problem with path names containing blanks (driver executable).
- Cleaned command line and argument handling (driver executable).
- Fixed a severe memory leak.
- Fixed a bug, if a C++ keyword was used as a macro name or macro parameter 
  name, which prevented the macro recognition and expansion to function 
  properly.
- Implemented the WAVE_SUPPORT_MS_EXTENSIONS compiler switch for the re2c 
  generated lexer too.
- Fixed a problem, which caused an internal T_PLACEHOLDER token to show up 
  outside the macro replacement engine.
- Fixed a problem with macro #include directives, which prevents to find the 
  file to include, if after the macro expansion the token sequence representing 
  the filename began or ended with at least one whitespace token.
- Fixed a problem, which caused a false error message if the '#' character was
  to be concatenated with an arbitrary other token.
- The concatenation of a whitespace token with an arbitrary other token was 
  reported as illegal token pasting (but it is certainly not).
   
Sat Mar 15 21:43:56     2003
- Added a default constructor to the wave::util::file_position template.
- Report the concatenation of unrelated tokens as an error.
- Finished the documentation.

Fri Mar 14 20:14:18     2003
- More work on documentation
- Changed file_position to expose accessor functions (the member variables are
  marked as private now). This opens up the possibility to provide another 
  file_position implementation, which may be optimized in some way.
- Fixed a problem with the token name table, the alternate and trigraph token
  names were printed incorrectly.
- Fixed a bug, which prevented the correct recognition of 'defined X' (without 
  parenthesises).
- Fixed a bug, which allowed to redefine and undefine the predefined name 
  'defined'.
- Fixed a bug, which prevents the correct recognition of a macro based #include 
  directive, if it expands to something like #include <...>.
- Fixed a bug, which prevented the recognition of duplicate macro parameter
  names.
- Removed the insertion of additional whitespace inside of string literals 
  (during stringizing).
  
Wed Mar 12 19:16:40     2003
- Fixed a bug, which prevented the instantiation of the wave::context object 
  with auxiliary iterators. The token type isn't coupled anymore with the 
  iterator type.
  This required some changes in the interface:
    - The wave::context object now has three template parameters (the iterator
      type, the token type and the input policy type)
    - The token type does not have the iterator type as it's template parameter
      anymore.
- Implemented a new position_iterator template on top of the iterator_adaptor<>
  template to make it work even for input_iterator type iterators.
- Fixed a bug in the regular expressions for the Slex lexer.
- The function 'set_sys_include_delimiter()' was renamed to 
  'set_sysinclude_delimiter()' to better fit the naming scheme of the other 
  functions.
- Wrote more documentation
- Unified the different token definitions of the lexers, so that there is only
  one token type left. This required some changes in the interface:
    - There is no need anymore to explicitly specify the namespace of the token
      type to use.
- Added the command line option -P to the Wave driver program, which predefines 
  a macro (i.e. defines it such, that is _not_ undefinable through an #undef
  directive from inside the preprocessed program).

Sat Mar  8 07:46:43     2003
- Released Wave 0.9.0

Thu Mar  6 20:02:44     2003
- Compiled Wave with IntelV7.0/DinkumwareSTL (from VC6sp5)
- Fixed new compilation problems with gcc -Wall
- Fixed the list_includes and cpp_tokens samples to compile and link correctly.
- Fixed a bug, where a wrong filename was reported by the generated #line 
  directive.
- Fixed a bug, where the __FILE__ macro was expanded without '\"' around the
  filename.
- The generated #line directives and the expanded __FILE__ macro now report
  the filename in a native (to the system) format. Additionally the generated
  string literals are now escaped correctly.

Wed Mar  5 21:11:14     2003
- Reorganized the directory structure to mirror the namespace structure of the
  library
- Fixed a bug, where the complete input after the first found #include 
  directive were eaten up.
- Fixed a bug, where the __LINE__ macro expanded to a incorrect linenumber, if
  the __LINE__ macro was encountered on a line after a '\\' '\n' sequence.

Tue Mar  4 11:50:24     2003
- The new name of the project is 'Wave'.
- Adjusted namespaces, comments etc. to reflect the new name.
- Added the command line option -U [--undefine], which allows to remove one of 
  the predefined macros (except __LINE__, __FILE__, __DATE__, __TIME__, 
  __STDC__ and __cplusplus)

Sun Mar  2 20:10:04     2003
- Fixed a bug while expanding macros without any definition part (empty macros)
- The pp-iterator will not emit a newline for every recognized preprocessing
  directive anymore. The generated output is much more condensed this way. 
- The pp-iterator now emits #line directives at appropriate places.
- Added an additional parser to the library, which may be used to parse macros
  given in the command line syntax, i.e. something like 'MACRO(x)=definition'.
- Added the possibility to the cpp driver sample, to add macros from the 
  command line through the -D command line switch.
- Martin Wille contributed a test script to allow automatic testing of the 
  cpp driver sample by feeding all files contained in the test_files directory
  through the cpp driver and comparing the generated output with the 
  corresponding expectations.
- Added config file support to allow for predefined option sets (for instance
  for the emulation of other compilers)
- Changed the way, how include paths are defined. It resembles now the 
  behaviour of gcc. 
  Any directories specified with '-I' options before an eventually given '-I-' 
  option are searched only for the case of '#include "file"', they are not 
  searched for '#include <file>' directives. If additional directories are 
  specified with '-I' options after a '-I-' option was given, these directories 
  are searched for all '#include' directives. In addition, the '-I-' option 
  inhibits the use of the current directory as the first search directory for 
  '#include "file"'. Therefore, the current directory is searched only if it is 
  requested explicitly with '-I.'. Specifying both '-I-' and '-I.' allows to 
  control precisely which directories are searched before the current one 
  and which are searched after.
- Added config file support to the cpp driver.
- stored not only the current 'name' of a file (given eventually by a #line
  directive) but in parallel the actual full file system name of this file too.
  
Tue Feb 25 21:44:19     2003
- Fixed the warnings emitted by gcc -Wall.
- Fixed a bug in the cpp grammar, which causes to failing the recognition of 
  certain preprocessor directives if at the end of this directive were placed 
  a C++ comment.
- Simplified and extended the insertion of whitespace tokens at places, where
  otherwise two adjacent tokens would form a new different token, if 
  retokenized.

Mon Feb 24 19:13:46     2003
- defined() functionality was broken
- added missing typename keywords
- added missing using namespace statements, where appropriate
- added a warning, when a predefined macro is to be undefined (by an #undef 
  directive)
- removed the 'compile in C mode' hack for the re2c generated lexer (VC7.1 
  (final beta) is not able to compile it with optimizations switched on 
  anyway :( )
- compiled with gcc 3.2 and Intel V7.0 (20030129Z)

Sun Feb 23 23:39:33  2003
- Fixed a couple of 'missing typename' bugs (thanks to Martin Wille)
- Added code to insert whitespace at places, where otherwise two adjacent 
  tokens would form a new different token, if retokenized.
- Fixed a severe macro expansion bug.
- Added the handling of invalid or not allowed universal character values 
  inside of string literals and character literals.

Sat Feb 22 20:52:06  2003
- Bumped version to 0.9.0
- Added test for invalid or not allowed universal character values (see
  C++ Standard 2.2.2 [lex.charset] and Annex E)
- Fixed a bug with newlines between a macro name and the opening parenthesis 
  during the macro expansion and a bug with newlines inside the parameter list
  during the macro expansion.
- Added the following predefined macros:
    __SPIRIT_PP__
        expands to the version number of the pp-iterator lib (i.e. 0x0090 for 
        V0.9.0)
    __SPIRIT_PP_VERSION__
        expands to the full version number of the pp-iterator lib (i.e.
        0x00900436 for V0.9.0.436)
    __SPIRIT_PP_VERSION_STR__
        expands to the full version string of the pp-iterator lib (i.e. 
        "0.9.0.436")
  
Fri Feb 21 22:09:04  2003 (feature complete!)
- Allowed to optionally compile the Re2c generated lexer in 'C' mode, because 
  at least the VC7.1 (final beta) compiler has problems to compile it in 'C++'
  mode with optimizations switch on
- Implemented #error and #warning (optional) directives (C++ standard 16.5). 
  Additionally there are now allowed the following preprocessor configuration 
  constants:
    CPP_PREPROCESS_ERROR_MESSAGE_BODY
        if defined, preprocesses the message body of #error and #warning  
        directives to allow for better diagnostics.
    CPP_SUPPORT_WARNING_DIRECTIVE
        if defined, then the #warning directive will be recognized such, that
        a warning with the given message will be issued
- Adjusted the error handling for the Re2c generated C++ lexer, so that any
  error inside the lexer is now propagated as an cpplexer_exception.
- Implemented the #line directive (C++ standard 16.4)
- Implemented #pragma directive (C++ standard 16.6)
  Additionally there are now allowed the following preprocessor configuration 
  constants:
    CPP_RETURN_PRAGMA_DIRECTIVES
        if defined, then the whole pragma directive is returned as a token
        sequence to the caller, if not defined the whole pragma directive is 
        skipped
    CPP_PREPROCESS_PRAGMA_BODY
        if defined, then the #pragma body will be preprocessed 
- Implemented #include directive with macro arguments (C++ standard 16.2.4)
- Made the namespace structure finer granulated to leave only the main 
  interface classes in the main namespace cpp. All other classes are moved into
  sub-namespaces to reflect the logical dependencies
- Reorganized the public interface of the context<> template class, made all
  non relevant functions into the protected.
- Implemented predefined macros (__LINE__ et.al.) (C++ standard 16.8)
- Further documentation work
  
Wed Feb 19 23:44:47  2003
- Corrected a lot of bugs in the macro expansion engine, which now should be 
  conformant to the C++ standard.
- # (null) directive (C++ standard 16.7)

Sun Feb 16 08:40:38  2003
- Added a macro expansion engine which expands macros with arguments 
  C++ standard 16.3 [cpp.replace]
- Added a new sample: cpp_tokens. This sample preprocesses a given file and
  prints out the string representations of all tokens returned from the pp 
  iterator
- Added documentation (to be continued!)
- Added a couple of small test files to test elementary functionality
  (the tests mainly were contributed by Paul Mensonides)
- The main cpp sample is now a simple preprocessor driver program, which 
  outputs the string representation of the preprocessed input stream. Use 
  cpp --help to get a hint, how to use it.
- Fixed a bug in the preprocessor grammar which failed to recognize a pp 
  statement, if there was a C++ comment at the end of the line
- Added '#' operator (C++ standard 16.3.2) [cpp.stringize]
- Fixed a bug in the slex based C++ lexer to handle the concatenation 
  characters correctly ('\\' followed by a '\n')

Sun Feb  9 23:01:00  2003
- Improved error handling for #if et.al.
- Fixed a pair of lexer errors
- Implemented the #if/#elif statements, the sample now contains a complete C++ 
  expression evaluation engine (for the calculation of the outcome of the 
  #if/#elif statement conditions)
- Implemented macro replacement (with parameters)
- Implemented the '##' [cpp.concat] operator
- Implemented the defined() [cpp.cond] operator

Sun Feb  2 23:28:24  2003
- Implemented the  #define, #undef, #ifdef, #ifndef, #else and #endif 
  statements
- Added optional parse tree output as xml stream (controlled through the config
  pp constant CPP_DUMP_PARSE_TREE)

Fri Jan 31 21:30:55  2003
- Fixed different minor issues and a border case (#include statement at the 
  last line of a included file)

Wed Jan 29 21:13:32  2003
- Fixed exception handling to report the correct error position
- Fixed another bug in the stream position calculation scheme
- Added a more elaborate sample 'list_includes' which lists the dependency
  information for a given source file (see test/list_includes/readme.txt).

Sat Jan 18 22:01:03  2003
- Fixed a bug in the stream position calculation scheme
- Made cpp::exceptions more standard conformant (added 'throw()' at appropriate 
  places)
- Overall housekeeping :-)

Wed Jan 15 21:54:20  2003
Changes since project start (still 0.5.0)
- Added #include <...> and #include "..." functionality
- pp directives are now generally recognized 
- Decoupled the C++ lexers and the pp grammar to separate compilation
  units (optionally) to speed up compilation (a lot!)

Thu Jan  2 12:39:30  2003
A completely new version 0.5.0 of the C preprocessor was started. It's a 
complete rewrite of the existing code base. The main differences are:
- The preprocessor is now implemented as an iterator, which returns the 
  current preprocessed token from the input stream.
- The preprocessing of include files isn't implemented through recursion
  anymore. This follows directly from the first change. As a result of this
  change the internal error handling is simplified.
- The C preprocessor iterator itself is feeded by a new unified C++ lexer 
  iterator. BTW, this C++ lexer iterator could be used standalone and is not 
  tied to the C preprocessor. There are two different C++ lexers implemented 
  now, which are functionally completely identical. These expose a similar
  interface, so the C preprocessor could be used with both of them.
- The C++ lexers integrated into the C preprocessor by now are:
    Slex:   A spirit based table driven regular expression lexer (the slex 
            engine originally was written by Dan Nuffer and is available as a
            separate Spirit sample).
    Re2c:   A C++ lexer generated with the help of the re2c tool. This C++
            lexer was written as a sample by Dan Nuffer too.
  It isn't hard to plug in additional different C++ lexers. There are plans to
  integrate a third one written by Juan Carlos Arevalo-Baeza, which is 
  available as a Spirit sample.
  
-------------------------------------------------------------------------------
Tue Feb 12 22:29:50  2002
Changes from 0.2.3 to 0.2.4:
- Moved XML dumping functions to the main Spirit directory
- Fixed operator '##', it was not correctly implemented somehow :-(

Sun Feb 10 21:07:19  2002
Changes from 0.2.2 to 0.2.3:
- Implemented concatenation operator '##' (cpp.concat)
- Removed defined() functionality for Intel compiler (it ICE's) until this 
  issue is resolved
- Separated code for dumping a parse tree to XML for inclusion in the main
  Spirit headers

Thu Jan 17 23:51:21  2002
Changes from 0.2.1 to 0.2.2:
- Fixes to compile with gcc 2.95.2 and gcc 3.0.2 (thanks Dan Nuffer)
- Reformatted the grammars to conform to a single formatting guideline
- Assigned explicit rule_id's to the rules of cpp_grammar, so that the 
  access code to the embedded definition class is not needed anymore
- Fixed a remaining const problem

Tue Jan 15 23:40:40  2002
Changes from 0.2.0 to 0.2.1:
- Corrected handling of defined() operator
- In preprocessing conditionals undefined identifiers now correctly
  replaced by '0'
- Fixed several const problems
- Added parse_node_iterator for traversing one node in a parse_tree
  without going deeper down the hierarchy than one level (this is useful,
  if all inspected tokens arranged along a single node in the parse tree.
  The main difference to the parse_tree_iterator is, that the underlying
  iterator generally can be adjusted correctly after advancing the attached
  parse_node_iterator
- Fixed a problem with gcc 2.95.2, which doesn't have a <sstream> header
- Prepared usage of slex for lexer states

Sun Jan 13 10:21:16  2002
Changes from 0.1.0 to 0.2.0:
- Added operator 'defined()'
- Added directive '#warning'
- Corrected error reporting
- Added command line option -I- for finer control of the searched include
  directories (-I and -I- should now work as in gcc, see readme.html for 
  more info)
- Corrected conditional preprocessing (should be fully functional now)
- Fixed existing code base for changes made in parse tree support
- Moved parse tree utility functions to a separate header (prepared for 
  inclusion to the Spirit main library)