compiler-the-translators/grammar.y

/*           Syntax Analyzer with Bison (3.8.1)			  */
/*  (referenced Bison manual for file boilerplate [3.1])  */

// Prologue
%{
  #include <stdio.h>
  #include "symbol_table.c"
  extern int yylex(void);
  void yyerror(const char *err);
  extern char* yytext;
  extern int yychar;
  SymbolTable * st;
  char* cur_value;
  char* cur_type;
%}

%union {
	int integ;
	char * words;
}
//precedence order
%precedence RESERVE
%precedence RELEASE
%precedence DOT
%precedence SUB_OR_NEG
%precedence NOT
%left MUL
%left DIV
%left REM
%left ADD
//need subtraction only here
%left LESS_THAN
%left EQUAL_TO
%left AND
%left OR
%left ASSIGN

%token <words> ID 101
%token T_INTEGER
%token T_ADDRESS 202
%token T_BOOLEAN 203
%token T_CHARACTER 204
%token T_STRING 205
%token C_INTEGER 301
%token C_NULL 302
%token C_CHARACTER 303
%token C_STRING 304
%token C_TRUE 305
%token C_FALSE 306
%token WHILE 401
%token IF 402
%token THEN 403
%token ELSE 404
%token TYPE 405
%token FUNCTION 406
%token RETURN 407
%token EXTERNAL 408
%token AS 409
%token L_PAREN 501
%token R_PAREN 502
%token L_BRACKET 503
%token R_BRACKET 504
%token L_BRACE 505
%token R_BRACE 506
%token SEMI_COLON 507
%token COLON 508
%token COMMA 509
%token ARROW 510
/* %token ADD 601
%token SUB_OR_NEG 602
%token MUL 603
%token DIV 604
%token REM 605
%token LESS_THAN 606
%token EQUAL_TO 607
%token ASSIGN 608
%token NOT 609
%token AND 610
%token OR 611
%token DOT 612
%token RESERVE 613
%token RELEASE 614 */
%token COMMENT 700


%%

program: 
	prototype_or_definition_list;

prototype_or_definition_list:
	prototype prototype_or_definition_list
	| definition prototype_or_definition_list
	| prototype
	| definition
	;
prototype:
	L_PAREN EXTERNAL R_PAREN FUNCTION ID COLON ID;

definition:
	TYPE ID COLON dblock
	| TYPE ID COLON constant ARROW ID
	| TYPE ID COLON ID ARROW ID
	| ID parameter ASSIGN sblock
	;

parameter:
	L_PAREN ID R_PAREN
	| AS L_PAREN idlist R_PAREN
	;

idlist:
	ID COMMA idlist
	|ID
	;

sblock:
	L_BRACE {st = CreateScope(st,1,1);} statement_list {st = getParent(st);} R_BRACE
	| L_BRACE {st = CreateScope(st,1,1);} dblock statement_list {st = getParent(st);} R_BRACE
	;

dblock:
	L_BRACKET declaration_list R_BRACKET;

declaration_list:
	declaration {CreateEntry(st,cur_type,cur_value);} SEMI_COLON declaration_list
	| declaration {CreateEntry(st,cur_type,cur_value);}
	;

declaration:
	ID COLON ID {cur_value = strdup($1);cur_type = strdup($3);};

statement_list:
	compound_statement statement_list
	| compound_statement
	| simple_statement SEMI_COLON statement_list
	| simple_statement SEMI_COLON
	;

compound_statement:
	WHILE L_PAREN expression R_PAREN sblock
	| IF L_PAREN expression R_PAREN THEN sblock ELSE sblock
	| sblock
	;

simple_statement:
	assignable ASSIGN expression
	| RETURN expression
	;

assignable:
	ID
	| assignable ablock
	| assignable DOT ID
	;

expression:
	constant
	| UnaryOperator expression
	| assignable
	| constant binaryOperator expression
	| L_PAREN expression R_PAREN
	| memOp assignable
	;

ablock:
	L_PAREN argument_list R_PAREN;

argument_list:
	expression COMMA argument_list
	| expression
	;

UnaryOperator:
	SUB_OR_NEG
	| NOT
	;

memOp:
	RESERVE
	| RELEASE
	;

binaryOperator:
	ADD
	| SUB_OR_NEG
	| MUL
	| DIV
	| REM
	| AND
	| OR
	| LESS_THAN
	| EQUAL_TO
	;

constant:
	C_STRING
	| C_INTEGER
	| C_NULL
	| C_CHARACTER
	| C_TRUE
	| C_FALSE
	;
//
%%

void yyerror(const char *err) {
    fprintf(stderr, "Error: %s\n", err);
}

int main() {
	cur_value = NULL;
	cur_type = NULL;
	st=CreateScope(NULL,1,1);
	int a;
	while ((a = yyparse()) != EOF){
		printf("%d = a: yytext = %s: yychar = %d\n", a, yytext, yychar);
		if(yytext[0] == '!'){
			print_symbol_table(getAncestor(st),stdout);
			break;
		}
	}
	return 0;
}