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%{
#include <stdio.h>
#include <stdlib.h>
#include "src/util/c99_stdint.h"
#include "src/parse/ast.h"
#include "lib/lex.h"
// disable certain GCC and/or Clang warnings, as we have no control over
// autogenerated code (Clang also understands '#pragma GCC')
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wpragmas"
#pragma GCC diagnostic ignored "-Wconversion"
#pragma GCC diagnostic ignored "-Wsign-conversion"
#pragma GCC diagnostic ignored "-Wunused-macros"
#pragma GCC diagnostic ignored "-Wmissing-variable-declarations"
#pragma GCC diagnostic ignored "-Wunreachable-code"
#pragma GCC diagnostic ignored "-Wunreachable-code-break"
using namespace re2c;
extern "C" {
int yylex(const char *&pattern);
void yyerror(const char *pattern, const char*) RE2C_ATTR((noreturn));
} // extern "C"
%}
%lex-param {const char *&pattern}
%parse-param {const char *&pattern}
%start regexp
%union {
const re2c::AST *regexp;
re2c::ASTBounds bounds;
};
%token TOKEN_COUNT
%token TOKEN_ERROR
%token TOKEN_REGEXP
%type <regexp> TOKEN_REGEXP regexp expr term factor primary
%type <bounds> TOKEN_COUNT
%%
regexp: expr { regexp = $$; };
expr
: term
| expr '|' term { $$ = ast_alt($1, $3); }
;
term
: factor
| factor term { $$ = ast_cat($1, $2); } // in POSIX concatenation is right-associative
;
factor
: primary
| primary '*' { $$ = ast_iter($1, 0, AST::MANY); }
| primary '+' { $$ = ast_iter($1, 1, AST::MANY); }
| primary '?' { $$ = ast_iter($1, 0, 1); }
| primary TOKEN_COUNT { $$ = ast_iter($1, $2.min, $2.max); }
;
primary
: TOKEN_REGEXP
| '(' ')' { $$ = ast_cap(ast_nil(NOWHERE)); }
| '(' expr ')' { $$ = ast_cap($2); }
;
%%
#pragma GCC diagnostic pop
extern "C" {
void yyerror(const char *pattern, const char *msg)
{
fprintf(stderr, "%s (on RE %s)", msg, pattern);
exit(1);
}
int yylex(const char *&pattern)
{
return lex(pattern);
}
} // extern "C"
namespace re2c {
const AST *parse(const char *pattern)
{
yyparse(pattern);
return regexp;
}
} // namespace re2c
|
