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/*
* This file is part of flex.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE.
*/
%{
/* A template scanner file to build "scanner.c".
Run as:
test-lineno-nr # report flex's yylineno
test-lineno-nr 1 # report count_newlines(stdin)
*/
#include <stdio.h>
#include <stdlib.h>
#include "config.h"
%}
%option 8bit outfile="scanner.c" prefix="test"
%option nounput nomain noyywrap yylineno
%option warn
WORD [[:alpha:]]+
DIGIT [[:digit:]]
%%
/* The goal here is to test the yylineno processing by:
- providing some rules than CAN match newlines and
other rules that can NOT match newlines,
- matching several newlines in one rule,
- directly modifying yylineno.
*/
"yylineno++" yylineno++;
"yylineno--" yylineno--;
[[:blank:]]+
{WORD}
{DIGIT}+(\n{DIGIT}+)*
\n
.
<<EOF>> { printf("%d\n", yylineno);
yyterminate();
}
%%
/* returns number of '\n' characters in input, plus one.
This is what flex does, essentially. */
static int
count_newlines (FILE* in)
{
int n=1,c;
while ((c=fgetc(in)) != EOF)
if( c == '\n')
n++;
return n;
}
int main ( int, char**);
int
main ( argc, argv )
int argc;
char** argv;
{
if( argc > 1 )
printf("%d\n", count_newlines(stdin));
else{
yyin = stdin;
yyout = stdout;
yylex();
}
return 0;
}
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