flex-bison-in-action/analyzers/polynomials/polynomials.l

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This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

%{
#include "C:\Users\user\Desktop\УЧЕБА\6_СЕМ\КОМПИЛЯТОРЫ\flex_bison_test\analyzers\polynomials\poly_calc\poly_calc.h"
#include "polynomials.tab.h"
extern FILE *yyin;
char allowed_variable = 0;
int current_line_number = 1;
const char* INT_MAX_STR = "2147483646";
void yyerror(const char *s) {
fprintf(stderr, "Error at line %i: %s\n", current_line_number, s);
}
%}
%%
"print" { return PRINT; }
";" { return SEMICOLON; }
"=" { return EQUAL; }
[0-9]+ {
size_t len = strlen(yytext);
if (len > strlen(INT_MAX_STR)) {
yyerror("Number too large (max 2147483646)");
exit(-1);
} else if (len == strlen(INT_MAX_STR)) {
if (strcmp(yytext, INT_MAX_STR) > 0) {
yyerror("Number too large (max 2147483646)");
exit(-1);
}
}
init_polynomial(&yylval.poly);
add_term(&yylval.poly, atoi(yytext), 0);
return NUMBER;
}
[a-z] {
if (allowed_variable == 0) {
allowed_variable = yytext[0];
}
else if (yytext[0] != allowed_variable) {
yyerror("Bad variable in expression");
exit(1);
}
init_polynomial(&yylval.poly);
add_term(&yylval.poly, 1, 1);
return VARIABLE;
}
[A-Z] {
yylval.var_name = yytext[0];
return VAR_POLY;
}
[-+*^()] { return yytext[0]; }
[ \t] ;
\n { current_line_number++; }
. { yyerror("Unknown symbol");
exit(1);
}
%%
int yywrap() {
return 1;
}