ENH: Add rudamentary mathematical expression support

1 files changed, 171 insertions, 0 deletions

diff --git a/Source/cmExprParser.y b/Source/cmExprParser.y
new file mode 100644
index 0000000..485972c
--- /dev/null
+++ b/Source/cmExprParser.y
@@ -0,0 +1,171 @@
+%{
+/*=========================================================================
+
+  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 bison like this:
+
+  bison --yacc --name-prefix=cmExpr_yy --defines=cmExprParserTokens.h -ocmExprParser.cxx cmExprParser.y
+
+Modify cmExprParser.cxx:
+  - remove TABs
+  - add __HP_aCC to the #if test for yyerrorlab warning suppression
+
+*/
+
+/* Configure the parser to use a lexer object.  */
+#define YYPARSE_PARAM yyscanner
+#define YYLEX_PARAM yyscanner
+#define YYERROR_VERBOSE 1
+#define cmExpr_yyerror(x) \
+        cmExprError(yyscanner, x)
+#define yyGetParser (cmExpr_yyget_extra(yyscanner))
+
+/*-------------------------------------------------------------------------*/
+#include "cmExprParserHelper.h" /* Interface to parser object.  */
+#include "cmExprLexer.h"  /* Interface to lexer object.  */
+#include "cmExprParserTokens.h" /* Need YYSTYPE for YY_DECL.  */
+
+#include <math.h>
+
+/* Forward declare the lexer entry point.  */
+YY_DECL;
+
+/* Internal utility functions.  */
+static void cmExprError(yyscan_t yyscanner, const char* message);
+
+#define YYDEBUG 1
+//#define YYMAXDEPTH 100000
+//#define YYINITDEPTH 10000
+
+
+/* Disable some warnings in the generated code.  */
+#ifdef __BORLANDC__
+# pragma warn -8004 /* Variable assigned a value that is not used.  */
+#endif
+#ifdef _MSC_VER
+# pragma warning (disable: 4102) /* Unused goto label.  */
+# pragma warning (disable: 4065) /* Switch statement contains default but no case. */
+#endif
+%}
+
+/* Generate a reentrant parser object.  */
+%pure_parser
+
+/*-------------------------------------------------------------------------*/
+/* Tokens */
+%token exp_PLUS
+%token exp_MINUS
+%token exp_TIMES
+%token exp_DIVIDE
+%token exp_MOD
+%token exp_SHIFTLEFT
+%token exp_SHIFTRIGHT
+%token exp_OPENPARENT
+%token exp_CLOSEPARENT
+%token exp_OR;
+%token exp_AND;
+%token exp_XOR;
+%token exp_NOT;
+%token exp_NUMBER;
+
+/*-------------------------------------------------------------------------*/
+/* grammar */
+%%
+
+
+Start:
+exp
+{
+  yyGetParser->SetResult($<Number>1);
+}
+
+exp:
+bitwiseor
+{$<Number>$ = $<Number>1;}
+|
+exp exp_OR bitwiseor
+{$<Number>$ = $<Number>1 | $<Number>3;}
+
+bitwiseor:
+bitwisexor
+{$<Number>$ = $<Number>1;}
+|
+bitwiseor exp_XOR bitwisexor
+{$<Number>$ = $<Number>1 ^ $<Number>3;}
+
+bitwisexor:
+bitwiseand
+{$<Number>$ = $<Number>1;}
+|
+bitwisexor exp_AND bitwiseand
+{$<Number>$ = $<Number>1 & $<Number>3;}
+
+bitwiseand:
+term
+{$<Number>$ = $<Number>1;}
+|
+bitwiseand exp_PLUS term
+{$<Number>$ = $<Number>1 + $<Number>3;}
+|
+bitwiseand exp_MINUS term
+{$<Number>$ = $<Number>1 - $<Number>3;}
+
+term:
+factor
+{$<Number>$ = $<Number>1;}
+|
+term exp_TIMES factor
+{$<Number>$ = $<Number>1 * $<Number>3;}
+|
+term exp_DIVIDE factor
+{$<Number>$ = $<Number>1 / $<Number>3;}
+|
+term exp_MOD factor
+{$<Number>$ = $<Number>1 % $<Number>3;}
+
+factor:
+shift
+{$<Number>$ = $<Number>1;}
+|
+factor exp_SHIFTLEFT shift
+{$<Number>$ = $<Number>1 << $<Number>3;}
+|
+factor exp_SHIFTRIGHT shift
+{$<Number>$ = $<Number>1 >> $<Number>3;}
+
+
+shift:
+exp_NUMBER
+{$<Number>$ = $<Number>1;}
+|
+exp_OPENPARENT exp exp_CLOSEPARENT
+{$<Number>$ = $<Number>2;}
+;
+
+
+%%
+/* End of grammar */
+
+/*--------------------------------------------------------------------------*/
+void cmExprError(yyscan_t yyscanner, const char* message)
+{
+  yyGetParser->Error(message);
+}
+