parser.cup

java cup constructor to compiler

non_term_name_list ::=
	non_term_name_list
	COMMA
	new_non_term_id
	|
	new_non_term_id
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 


precedence_list ::= precedence_l | empty; 

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

precedence_l ::= precedence_l preced | preced;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

preced ::= 
	PRECEDENCE LEFT 
	{:
	  update_precedence(assoc.left);
	:}	
        terminal_list SEMI
	|
	PRECEDENCE RIGHT 
	{:
	  update_precedence(assoc.right);
	:}	
        terminal_list SEMI
	|
	PRECEDENCE NONASSOC 
	{:
	  update_precedence(assoc.nonassoc);
	:}	
        terminal_list SEMI
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

terminal_list ::= terminal_list COMMA terminal_id
	|
	terminal_id
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

terminal_id ::= term_id:sym
	{:	
	  add_precedence(sym);
	  RESULT = sym;
	:};
	  
/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

term_id ::= symbol_id:sym
        {:
	  /* check that the symbol_id is a terminal */
	  if (symbols.get(sym) == null)
	    {
	      /* issue a message */
	      lexer.emit_error("Terminal \"" + sym + 
			   "\" has not been declared");
	    }
          RESULT = sym;
         :};

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

start_spec ::= 
	START WITH nt_id:start_name 
	{: 
	  /* verify that the name has been declared as a non terminal */
	  non_terminal nt = (non_terminal)non_terms.get(start_name);
	  if (nt == null)
	    {
	      lexer.emit_error( "Start non terminal \"" + start_name + 
	  		         "\" has not been declared");
	    }
          else
	    {
	      /* remember the non-terminal for later */
	      start_nt = nt;

	      /* build a special start production */
	      new_rhs();
	      add_rhs_part(add_lab(new symbol_part(start_nt), "start_val"));
	      add_rhs_part(new symbol_part(terminal.EOF));
	      add_rhs_part(new action_part("RESULT = start_val;"));
	      emit.start_production = 
		     new production(non_terminal.START_nt, rhs_parts, rhs_pos);
	      new_rhs();
	    }
	:}
	SEMI
	|
	empty
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

production_list ::= production_list production | production;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

production ::=
	nt_id:lhs_id
	{:
	  /* lookup the lhs nt */
	  lhs_nt = (non_terminal)non_terms.get(lhs_id);

          /* if it wasn't declared, emit a message */
	  if (lhs_nt == null)
	    {
	      if (lexer.error_count == 0)
	        lexer.emit_error("LHS non terminal \"" + lhs_id + 
			       "\" has not been declared");
	    }

	  /* reset the rhs accumulation */
	  new_rhs();
	:}
	COLON_COLON_EQUALS
	{: :}
	rhs_list
	SEMI
	|
	error
	{: lexer.emit_error("Syntax Error"); :}
	SEMI
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

rhs_list ::= rhs_list BAR rhs | rhs;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

rhs ::= 
	prod_part_list PERCENT_PREC term_id:term_name 
	{:
	  java_cup.symbol sym = null;
	  if (lhs_nt != null) 
	    {
	      /* Find the precedence symbol */
	      if (term_name == null) {
		System.err.println("No terminal for contextual precedence");
		sym = null;
	      } else {
		sym = ((symbol_part)symbols.get(term_name)).the_symbol();
	      }
	      /* build the production */
	      production p;
	      if ((sym!=null) && (sym instanceof terminal)) {
		p = new production(lhs_nt, rhs_parts, rhs_pos,
				   ((terminal)sym).precedence_num(),
				   ((terminal)sym).precedence_side());
		((symbol_part)symbols.get(term_name)).the_symbol().note_use();
	      } else {
		System.err.println("Invalid terminal " + term_name + 
				   " for contextual precedence assignment");
		p = new production(lhs_nt, rhs_parts, rhs_pos);
	      }

	      /* if we have no start non-terminal declared and this is 
		 the first production, make its lhs nt the start_nt 
		 and build a special start production for it. */
              if (start_nt == null)
		{
		  start_nt = lhs_nt;

	          /* build a special start production */
	          new_rhs();
	          add_rhs_part(add_lab(new symbol_part(start_nt),"start_val"));
	          add_rhs_part(new symbol_part(terminal.EOF));
		  add_rhs_part(new action_part("RESULT = start_val;"));
		  if ((sym!=null) && (sym instanceof terminal)) {
		    emit.start_production = 
		      new production(non_terminal.START_nt, rhs_parts, 
				     rhs_pos, ((terminal)sym).precedence_num(),
				     ((terminal)sym).precedence_side());
		  } else {
		    emit.start_production = 
		      new production(non_terminal.START_nt, rhs_parts, rhs_pos);
		  }
	          new_rhs();
		}
	    }

	  /* reset the rhs accumulation in any case */
	  new_rhs();
	:}
	|
	prod_part_list 
	{: 
	  if (lhs_nt != null) 
	    {
	      /* build the production */
	      production p = new production(lhs_nt, rhs_parts, rhs_pos);

	      /* if we have no start non-terminal declared and this is 
		 the first production, make its lhs nt the start_nt 
		 and build a special start production for it. */
              if (start_nt == null)
		{
		  start_nt = lhs_nt;

	          /* build a special start production */
	          new_rhs();
	          add_rhs_part(add_lab(new symbol_part(start_nt),"start_val"));
	          add_rhs_part(new symbol_part(terminal.EOF));
		  add_rhs_part(new action_part("RESULT = start_val;"));
	          emit.start_production = 
		     new production(non_terminal.START_nt, rhs_parts, rhs_pos);

	          new_rhs();
		}
	    }
	  
	  /* reset the rhs accumulation in any case */
	  new_rhs();
	:} 
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

prod_part_list ::= prod_part_list prod_part | empty;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

prod_part ::=
	symbol_id:symid opt_label:labid
	{: 
	  /* try to look up the id */
	  production_part symb = (production_part)symbols.get(symid);

	  /* if that fails, symbol is undeclared */
	  if (symb == null)
	    {
	      if (lexer.error_count == 0)
	        lexer.emit_error("java_cup.runtime.Symbol \"" + symid + 
			       "\" has not been declared");
	    }
	  else
	    {
	      /* add a labeled production part */
	      add_rhs_part(add_lab(symb, labid));
	    }
	:}
	|
	CODE_STRING:code_str
	{: 
	  /* add a new production part */
	  add_rhs_part(new action_part(code_str));
	:}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

opt_label ::=
	COLON label_id:labid
	{: RESULT = labid; :}
	|
	empty
	{: RESULT = null; :}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

multipart_id ::=
	multipart_id DOT robust_id:another_id
	{: append_multipart(another_id); :}
	|
	robust_id:an_id
	{: append_multipart(an_id); :}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

import_id ::= 
	multipart_id DOT STAR
	{: append_multipart("*"); :}
	|
	multipart_id
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

type_id ::= multipart_id
	| type_id LBRACK RBRACK
	{: multipart_name = multipart_name.concat("[]"); :}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

new_term_id ::= 
	ID:term_id 
	{: 
	  /* see if this terminal has been declared before */
	  if (symbols.get(term_id) != null)
	    {
	      /* issue a message */
	      lexer.emit_error("java_cup.runtime.Symbol \"" + term_id + 
			   "\" has already been declared");
	    }
	  else
	    {
	      /* if no type declared, declare one */
	      if (multipart_name.equals("")) {
		append_multipart("Object");
	      }
	      /* build a production_part and put it in the table */ 
	      symbols.put(term_id, 
	        new symbol_part(new terminal(term_id, multipart_name)));
	    }
	:}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

new_non_term_id ::=
	ID:non_term_id
	{: 
	  /* see if this non terminal has been declared before */
	  if (symbols.get(non_term_id) != null)
	    {
	      /* issue a message */
	      lexer.emit_error( "java_cup.runtime.Symbol \"" + non_term_id + 
			                      "\" has already been declared");
	    }
	  else
	    {
	      if (multipart_name.equals("")) {
		append_multipart("Object");
	      }
	      /* build the non terminal object */
              non_terminal this_nt = 
		new non_terminal(non_term_id, multipart_name);

	      /* put it in the non_terms table */
	      non_terms.put(non_term_id, this_nt);

	      /* build a production_part and put it in the symbols table */ 
	      symbols.put(non_term_id, new symbol_part(this_nt));
	    }
	:}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

nt_id ::=
	ID:the_id
	{: RESULT = the_id; :}
	| error
	{:
		lexer.emit_error("Illegal use of reserved word");
		RESULT="ILLEGAL";
	:}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

symbol_id ::=
	ID:the_id
	{: RESULT = the_id; :}
	| error
	{:
		lexer.emit_error("Illegal use of reserved word");
		RESULT="ILLEGAL";
	:}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

label_id ::= 
	robust_id:the_id
	{: RESULT = the_id; :}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

robust_id ::= /* all ids that aren't reserved words in Java */
	ID:the_id	{: RESULT = the_id; :}
	/* package is reserved. */
	/* import is reserved. */
	| CODE		{: RESULT = "code"; :}
	| ACTION	{: RESULT = "action"; :}
	| PARSER	{: RESULT = "parser"; :}
	| TERMINAL	{: RESULT = "terminal"; :}
	| NON		{: RESULT = "non"; :}
	| NONTERMINAL   {: RESULT = "nonterminal"; :}
	| INIT		{: RESULT = "init"; :}
	| SCAN		{: RESULT = "scan"; :}
	| WITH		{: RESULT = "with"; :}
	| START		{: RESULT = "start"; :}
	| PRECEDENCE	{: RESULT = "precedence"; :}
	| LEFT		{: RESULT = "left"; :}
	| RIGHT		{: RESULT = "right"; :}
	| NONASSOC	{: RESULT = "nonassoc"; :}
	| error
	{:
		lexer.emit_error("Illegal use of reserved word");
		RESULT="ILLEGAL";
	:}
	;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

non_terminal ::= NON TERMINAL | NONTERMINAL;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

opt_semi ::= /* nothing */
	| SEMI;

/*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . */ 

empty ::= /* nothing */;

/*----------------------------------------------------------------*/