lcmm.l

使用yacc和lex编写的cmm语言的词法分析和语法分析程序.

%{

#include <stdio.h>
#include "y.tab.h"

void comment();

%}

D   [0-9]
L  [a-zA-Z]

%option yylineno
%%

"/*"                    {comment();}

"int"                   {return INT;}
"real"                  {return REAL;}
"while"                 {return WHILE;}
"write"                 {return WRITE;}
"read"                  {return READ;}
"if"                    {return IF;}
"else"                  {return ELSE;}

{L}({L}|{D}|"_")*       {return IDENTIFIER;}
{D}+                    {return CONSTANT;}
{D}*"."{D}+|{D}+"."{D}* {return CONSTANT;}

">="                    {return GE_OP;}
"<="                    {return LE_OP;}
"=="                    {return EQ_OP;}
"!="                    {return NE_OP;}
"&&"                    {return AND_OP;}
"||"                    {return OR_OP;}

'&'                     {return '&';}
'^'                     {return '^';}
'|'                     {return '|';}
">"                     {return '>';}
"<"                     {return '<';}
"="                     {return '=';}
"+"                     {return '+';}
"-"                     {return '-';}
"*"                     {return '*';}
"/"                     {return '/';}
"("                     {return '(';}
")"                     {return ')';}
"{"                     {return '{';}
"}"                     {return '}';}
"["                     {return '[';}
"]"                     {return ']';}
";"                     {return ';';}
":"                     {return ':';}
","                     {return ',';}

[ \t\n\v\f]+            { /* ignore whitespace */ }
.                       { /* ignore bad characters */ } 
%%

/** 
 * @brief  蹇界暐娉ㄩ噴閲岀殑鎵