scan.l

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/**************************************************************************** 
scan.l 
ParserWizard generated Lex file. 

****************************************************************************/ 
%{ 
#include "globals.h" 
#include "util.h" 
#include "scan.h" 
#include "parse.h" 

char tokenString[MAXTOKENLEN+1]; 
%} 

%include { 
#define MAXTOKENLEN 40 

extern char tokenString[MAXTOKENLEN+1]; 

TokenType getToken(void); 
} 

///////////////////////////////////////////////////////////////////////////// 
// declarations section 

letter [_a-zA-Z] 
letnum [_a-zA-Z0-9] 
identifier {letter}{letnum}* 
digit [0-9] 
number {digit}+ 
fnumber {number}"."{number} 
constchar '.' 
newline \n 
whitespace [ \t]+ 

%% 

///////////////////////////////////////////////////////////////////////////// 
// rules section 

"int" {return INT;} 
"float" {return FLOAT;} 
"char" {return CHAR;} 
"void" {return VOID;} 
"if" {return IF;} 
"else" {return ELSE;} 
"while" {return WHILE;} 
"continue" {return CONTINUE;} 
"break" {return BREAK;} 
"return" {return RETURN;} 
"+" {return PLUS;} 
"-" {return SUB;} 
"*" {return MUT;} 
"/" {return DIV;} 
"<" {return LT;} 
"<=" {return LE;} 
">" {return GT;} 
">=" {return GE;} 
"==" {return EQ;} 
"!=" {return NEQ;} 
"&amt;&amt;" {return AND;} 
"||" {return OR;} 
"!" {return NOT;} 
"=" {return ASSIGN;} 
";" {return SEMI;} 
"," {return COMMA;} 
"(" {return LP;} 
")" {return RP;} 
"[" {return LSP;} 
"]" {return RSP;} 
"{" {return LFP;} 
"}" {return RFP;} 
{identifier} {return ID;} 
{number} {return NUM;} 
{fnumber} {return FNUM;} 
{constchar} {return SCHAR;} 
{newline} {lineno++;} 
{whitespace} {} 
"//" { char c; 
while ((c = yyinput()) != '\n') 
if (c == EOF) return ENDFILE; 
yyunput(c); 
} 
"/*" { char c; 
int done = FALSE; 
do { 
while ((c = yyinput()) != '*') 
if (c == EOF) return ERROR; 
while ((c = yyinput()) == '*'); 
if (c == '/') done = TRUE; 
} while (!done); 
} 
. {return ERROR;} 


%%

///////////////////////////////////////////////////////////////////////////// 
// programs section 

TokenType getToken(void) 
{ 
static int firstTime = TRUE; 
TokenType currentToken; 
if (firstTime) { 
firstTime = FALSE; 
lineno++; 
yyin = source; 
yyout = listing; 
} 
currentToken = yylex(); 
strncpy(tokenString, yytext, MAXTOKENLEN); 
if (TraceScan) { 
lineno = yylineno; 
fprintf(listing,"\t%d: ",lineno); 
printToken(currentToken,tokenString); 
} 
return currentToken; 
}