anchor.diff:  	| variable
   	| STRINGLITERAL
   	| function
  -	| type;
  +	| type_;
   
   integer: ('+' | '-')? INTEGER;
   
  
positive.code: /*
   BSD License
   
   Copyright (c) 2021, Tom Everett All rights reserved.
   
   Redistribution and use in source and binary forms, with or without modification, are permitted
   provided that the following conditions are met:
   
   1. Redistributions of source code must retain the above copyright notice, this list of conditions
   and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the documentation and/or other
   materials provided with the distribution. 3. Neither the name of Tom Everett nor the names of its
   contributors may be used to endorse or promote products derived from this software without specific
   prior written permission.
   
   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
   IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
   FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
  
negative.code: 
  declaration_statements: declaration_statement+;
  
  declaration_statement: type_ ID ';';
  
  type_: 'int' | 'dfa' | 'nfa' | 'regex' | 'bool' | 'string';
  
  program_block: 'program' '{' statements '}';
  
  