text: 
  const gelex = require('gelex');
  const ldef = gelex.definition();
  
  const TokenType = { Name: 'name', Integer: 'integer', String: 'string', Delimiter: 'delimiter', Operator: 'operator' };
  
  ldef.define(TokenType.Integer, '[0-9][0-9]*');
  ldef.define(TokenType.Name, '[a-zA-Z_][a-zA-Z0-9_]*');
  ldef.define(TokenType.Delimiter, '().'.split(''));
  ldef.define(TokenType.Operator, "'+-*/".split(''));
  ldef.defineText(TokenType.String, '"', '"');
  ldef.defineComment(';');
  
  function createLexer(text) {
      return ldef.lexer(text);
  }
  
  module.exports = {
      lexer: createLexer,
      TokenType: TokenType
  }
  
  
  