aoc-2022/day_1/lexer.l
2022-12-25 21:15:50 +01:00

53 lines
1.1 KiB
C

%{ /* -*- C -*- */
#include <stdio.h>
#include <stdlib.h>
#include "parser.h"
%}
%option warn nodefault
/* makes the scanner terminate after reaching <<EOF>> instead of assuming a new input was provided */
%option noyywrap
/* disable some unused functionality, add scanner tracking */
%option nounput noinput batch debug
/* gimme a reentrant parser (overkill but more pure) */
%option reentrant
%option bison-bridge
NL [\n]
NUM [0-9]
%%
{NL} {
return NEWLINE;
}
{NUM}+ {
unsigned num = strtoul(yytext, NULL, 10);
printf("number: %d\n", num);
yylval->num = num;
return NUMBER;
}
<<EOF>> {
return END_OF_FILE;
}
. {
printf("[error] Encountered unexpected token %s\n", yytext);
return 0;
}
%%
/*int main() {*/
/*std::cout << "hello" << std::endl;*/
/*yyFlexLexer scanner;*/
/*scanner.yylex();*/
/*std::cout << "done" << std::endl;*/
/*return 0;*/
/*}*/