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%code requires{
#include "ast.hpp"
extern const Expression *g_root; // A way of getting the AST out
//! This is to fix problems when generating C++
// We are declaring the functions provided by Flex, so
// that Bison generated code can call them.
int yylex(void);
void yyerror(const char *);
}
// Represents the value associated with any kind of
// AST node.
%union{
const Expression *expr;
double number;
std::string *string;
}
%token T_KEYWORD T_IDENTIFIER //T_CONSTANT T_OPERATOR T_LCBRACKET T_RCBRACKET
%type <expr> STMNT_LIST STMNT COMP_STMNT EXPR_STMNT SLCT_STMNT ITR_STMNT JMP_STMNT
%type <number> T_CONSTANT
%type <string> T_KEYWORD T_IDENTIFIER T_OPERATOR
%start ROOT
%%
ROOT : STMNT_LIST { g_root = $1; }
STMNT_LIST : STMNT
| STMNT_LIST STMNT
STMNT : COMP_STMNT
| EXPR_STMNT
| SLCT_STMNT
| ITR_STMNT
| JMP_STMNT
COMP_STMNT : STMNT_LIST
%%
const Expression *g_root; // Definition of variable (to match declaration earlier)
const Expression *parseAST() {
g_root = 0;
yyparse();
return g_root;
}
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