Bruno BELANYI
171ef10a6d
All checks were successful
continuous-integration/drone/push Build is passing
This cleans up one of my major pain points with the Meson way of doing things. The Meson solution to have nice includes would have been to create an `include/<name>` directory per library I create...
101 lines
2 KiB
Plaintext
101 lines
2 KiB
Plaintext
// At least 3.2 to get rid of `stack.hh`
|
|
%require "3.2"
|
|
// Let's be modern
|
|
%language "C++"
|
|
|
|
// LALR is fine for our purposes
|
|
%skeleton "lalr1.cc"
|
|
|
|
// Write a header with our parser-related declarations
|
|
%defines
|
|
|
|
// Safer than unions...
|
|
%define api.value.type variant
|
|
// Define constructors for each token
|
|
%define api.token.constructor
|
|
|
|
// Ambiguity is forbidden
|
|
%expect 0
|
|
|
|
// Prefix all the tokens with TOK_ to avoid colisions.
|
|
%define api.token.prefix {TOK_}
|
|
// Track locations
|
|
%locations
|
|
|
|
// Enable parse tracing
|
|
%define parse.trace
|
|
// Give detailled error messages
|
|
%define parse.error detailed
|
|
// Correct look-ahead to avoid erroneous error messages
|
|
%define parse.lac full
|
|
|
|
// Code that should be in the header
|
|
%code requires {
|
|
// Forward declare our driver
|
|
namespace abacus::parse {
|
|
class ParserDriver;
|
|
} // namespace abacus::parse
|
|
|
|
#include "bignum/bignum.hh"
|
|
}
|
|
|
|
%code provides {
|
|
// Forward ParserDriver to scanner
|
|
#define YY_DECL \
|
|
yy::parser::symbol_type yylex(::abacus::parse::ParserDriver& drv)
|
|
YY_DECL;
|
|
}
|
|
|
|
// Only include the actual ParserDriver class declaration in source code
|
|
%code {
|
|
#include "parser-driver.hh"
|
|
}
|
|
|
|
// Use the driver to carry context back-and-forth
|
|
%param { abacus::parse::ParserDriver& drv }
|
|
|
|
%token EOF 0 "end-of-file"
|
|
|
|
%token <abacus::bignum::BigNum> NUM "number"
|
|
|
|
// Use `<<` to print everything
|
|
%printer { yyo << $$; } <*>;
|
|
|
|
%token
|
|
PLUS "+"
|
|
MINUS "-"
|
|
TIMES "*"
|
|
DIVIDE "/"
|
|
LPAREN "("
|
|
RPAREN ")"
|
|
|
|
// Let's define the usual PEMDAS rules
|
|
%left PLUS MINUS
|
|
%left TIMES DIVIDE
|
|
%precedence UNARY
|
|
|
|
%type <abacus::bignum::BigNum> input exp
|
|
|
|
%%
|
|
|
|
input:
|
|
exp EOF { drv.result() = $1; }
|
|
;
|
|
|
|
exp:
|
|
NUM { $$ = $1; }
|
|
| exp PLUS exp { $$ = $1 + $3; }
|
|
| exp MINUS exp { $$ = $1 - $3; }
|
|
| exp TIMES exp { $$ = $1 * $3; }
|
|
| exp DIVIDE exp { $$ = $1 / $3; }
|
|
| PLUS exp %prec UNARY { $$ = $2; }
|
|
| MINUS exp %prec UNARY { $$ = -$2; }
|
|
| LPAREN exp RPAREN { $$ = $2; }
|
|
;
|
|
|
|
%%
|
|
|
|
void yy::parser::error(location_type const& l, std::string const& m) {
|
|
std::cerr << l << ": " << m << '\n';
|
|
}
|