ENH: Add rudamentary mathematical expression support

1 files changed, 104 insertions, 0 deletions

diff --git a/Source/cmExprLexer.in.l b/Source/cmExprLexer.in.l
new file mode 100644
index 0000000..7e6b6cd
--- /dev/null
+++ b/Source/cmExprLexer.in.l
@@ -0,0 +1,104 @@
+%{
+/*=========================================================================
+
+  Program:   CMake - Cross-Platform Makefile Generator
+  Module:    $RCSfile$
+  Language:  C++
+  Date:      $Date$
+  Version:   $Revision$
+
+  Copyright (c) 2002 Kitware, Inc., Insight Consortium.  All rights reserved.
+  See Copyright.txt or http://www.cmake.org/HTML/Copyright.html for details.
+
+     This software is distributed WITHOUT ANY WARRANTY; without even
+     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+     PURPOSE.  See the above copyright notices for more information.
+
+=========================================================================*/
+/*
+
+This file must be translated to C and modified to build everywhere.
+
+Run flex like this:
+
+  flex --prefix=cmExpr_yy --header-file=cmExprLexer.h -ocmExprLexer.cxx cmExprLexer.in.l
+
+Modify cmExprLexer.cxx:
+  - remove TABs
+  - remove "yyscanner" argument from these methods:
+      yy_fatal_error, yyalloc, yyrealloc, yyfree
+  - remove all YY_BREAK lines occurring right after return statements
+  - change while ( 1 ) to for(;;)
+
+Modify cmExprLexer.h:
+  - remove TABs
+  - remove the yy_init_globals function
+  - remove the block that includes unistd.h
+  - remove #line directives (avoids bogus warning on old Sun)
+
+*/
+
+#include "cmExprParserHelper.h"
+
+/* Disable some warnings.  */
+#if defined(_MSC_VER)
+# pragma warning ( disable : 4127 )
+# pragma warning ( disable : 4131 )
+# pragma warning ( disable : 4244 )
+# pragma warning ( disable : 4251 )
+# pragma warning ( disable : 4267 )
+# pragma warning ( disable : 4305 )
+# pragma warning ( disable : 4309 )
+# pragma warning ( disable : 4706 )
+# pragma warning ( disable : 4786 )
+#endif
+
+/* Disable features we do not need. */
+#define YY_NEVER_INTERACTIVE 1
+#undef ECHO /* SGI termios defines this differently. */
+#define ECHO
+
+/* Replace the lexer input function.  */
+#undef YY_INPUT
+#define YY_INPUT(buf, result, max_size) \
+  { result = yyextra->LexInput(buf, max_size); }
+
+/* Include the set of tokens from the parser.  */
+#include "cmExprParserTokens.h"
+
+
+#if defined( _WIN32 ) && !defined( __CYGWIN__ )
+/* Handle Windows properly */
+#  include <io.h>
+#  if defined( _MSC_VER )
+#    define isatty _isatty
+#  endif
+#  define YY_NO_UNISTD_H 1
+#endif
+
+/*--------------------------------------------------------------------------*/
+%}
+
+%option reentrant
+%option noyywrap
+%pointer
+
+%%
+
+[0-9][0-9]* { yylvalp->Number = atoi(yytext); return exp_NUMBER; } 
+
+"+" { return exp_PLUS; }
+"-" { return exp_MINUS; } 
+"*" { return exp_TIMES; } 
+"/" { return exp_DIVIDE; } 
+"%" { return exp_MOD; } 
+"\|" { return exp_OR; } 
+"&" { return exp_AND; } 
+"^" { return exp_XOR; } 
+"~" { return exp_NOT; } 
+"<<" { return exp_SHIFTLEFT; } 
+">>" { return exp_SHIFTRIGHT; } 
+"(" { return exp_OPENPARENT; }
+")" { return exp_CLOSEPARENT; }
+
+%%