Finished lexer for the parser

2 files changed, 55 insertions, 36 deletions

diff --git a/c_parser/src/c_lexer.flex b/c_parser/src/c_lexer.flex
index 670ec2b..833aa32 100644
--- a/c_parser/src/c_lexer.flex
+++ b/c_parser/src/c_lexer.flex
@@ -8,29 +8,49 @@ extern "C" int fileno(FILE *stream);
 
 %}
 
+KEYWORD auto|double|int|struct|break|else|long|switch|case|enum|register|typedef|char|extern|return|union|const|float|short|unsigned|continue|for|signed|void|default|goto|sizeof|volatile|do|if|static|while
+
+IDENTIFIER [_a-zA-Z][_a-zA-Z0-9]*
+
+OPERATOR [.][.][.]|[<>][<>][=]|[-][-]|[+][+]|[|][|]|[#][#]|[&][&]|[+\-*\/<>=!%^|&][=]|[<][<]|[->][>]|[<>&=+\/\-*(){}\[\]\.,%~!?:|^;]
+
+FRACTIONALCONSTANT (([0-9]*\.[0-9]+)|([0-9]+\.))
+EXPONENTPART ([eE][+-]?[0-9]+)
+
+FLOATINGSUFFIX ([flFL])
+INTEGERSUFFIX ([uU][lL]|[lL][uU]|[uUlL])
+
+DECIMALCONSTANT ([1-9][0-9]*)
+OCTALCONSTANT ([0][0-7]*)
+HEXCONSTANT ([0][xX][0-9A-Fa-f]+)
+
+CHARCONSTANT ('(([\\]['])|([^']))+')
+
+STRINGLITERAL ["](([\\]["])|([^"]))*["]
+
+WHITESPACE [ \t\r\n]+
+
+PREPROC [#][ ][0-9]+[ ]{STRINGLITERAL}[ 0-9]*
+
+ALL .
+
 %%
-[*]             { return T_TIMES; }
-[+]             { return T_PLUS; }
-[/]             { return T_DIVIDE; }
-[-]             { return T_MINUS; }
 
-[(]             { return T_LBRACKET; }
-[)]             { return T_RBRACKET; }
+{KEYWORD}   { yylval.string = new std::string(yytext); return T_KEYWORD; }
+
+{IDENTIFIER}    { yylval.string = new std::string(yytext); return T_IDENTIFIER; }
+
+{OPERATOR}  { yylval.string = new std::string(yytext); return T_OPERATOR; }
 
-log             { return T_LOG;   }
-exp             { return T_EXP; }
-sqrt            { return T_SQRT; }
+({HEXCONSTANT}|{OCTALCONSTANT}|{DECIMALCONSTANT})|{INTEGERSUFFIX}?	{ yylval.number=strtod(yytext, 0); return T_CONSTANT; }
 
-[-]?[0-9]+([.][0-9]*)? { yylval.number=strtod(yytext, 0); return T_NUMBER; }
-[a-z]+          { yylval.string=new std::string(yytext); return T_VARIABLE; }
+{WHITESPACE}		{ ; }
 
-[ \t\r\n]+		{;}
+.                   { fprintf(stderr, "Invalid token\n"); exit(1); }
 
-.               { fprintf(stderr, "Invalid token\n"); exit(1); }
 %%
 
-void yyerror (char const *s)
-{
-  fprintf (stderr, "Parse error : %s\n", s);
-  exit(1);
+void yyerror(char const *s) {
+     fprintf (stderr, "Parse error : %s\n", s);
+     exit(1);
 }
diff --git a/c_parser/src/c_parser.y b/c_parser/src/c_parser.y
index a00ab82..56fb961 100644
--- a/c_parser/src/c_parser.y
+++ b/c_parser/src/c_parser.y
@@ -1,30 +1,30 @@
 %code requires{
-  #include "ast.hpp"
 
-  #include <cassert>
+#include "ast.hpp"
 
-  extern const Expression *g_root; // A way of getting the AST out
+extern const Expression *g_root; // A way of getting the AST out
+
+//! This is to fix problems when generating C++
+// We are declaring the functions provided by Flex, so
+// that Bison generated code can call them.
+int yylex(void);
+void yyerror(const char *);
 
-  //! This is to fix problems when generating C++
-  // We are declaring the functions provided by Flex, so
-  // that Bison generated code can call them.
-  int yylex(void);
-  void yyerror(const char *);
 }
 
 // Represents the value associated with any kind of
 // AST node.
 %union{
-  const Expression *expr;
-  double number;
-  std::string *string;
+    const Expression *expr;
+    double number;
+    std::string *string;
 }
 
-%token T_TIMES T_PLUS T_DIVIDE T_MINUS T_LBRACKET T_RBRACKET T_LOG T_EXP T_SQRT T_NUMBER T_VARIABLE
+%token T_KEYWORD T_IDENTIFIER T_CONSTANT T_OPERATOR
 
 %type <expr> EXPR TERM FACTOR
-%type <number> T_NUMBER
-%type <string> T_VARIABLE T_LOG T_EXP T_SQRT FUNCTION_NAME
+%type <number> T_CONSTANT
+%type <string> T_KEYWORD T_IDENTIFIER T_OPERATOR
 
 %start ROOT
 
@@ -60,9 +60,8 @@ FUNCTION_NAME : T_LOG   { $$ = new std::string("log"); }
 
 const Expression *g_root; // Definition of variable (to match declaration earlier)
 
-const Expression *parseAST()
-{
-  g_root=0;
-  yyparse();
-  return g_root;
+const Expression *parseAST() {
+    g_root=0;
+    yyparse();
+    return g_root;
 }