lib/parse.js
function createSyntaxError (message, c) {
  if (c === undefined) {
    c = index - token.length;
  }
  let error = new SyntaxError(message + ' (char ' + c + ')');
  error['char'] = c;

  return error;
}
function createSyntaxError (message, c) {
  if (c === undefined) {
    c = index - token.length;
  }
  let error = new SyntaxError(message + ' (char ' + c + ')');
  error['char'] = c;

  return error;
}
function createSyntaxError ( message , c ) { if ( c === undefined ) { c = index - token . length ; } let error = new SyntaxError ( message + ' (char ' + c + ')' ) ; error [ 'char' ] = c ; return error ; }
Create an error
@param {string} message
@param {number} [c]  Optional index (character position) where the
error happened. If not provided, the start of
the current token is taken
@return {SyntaxError} instantiated error
@private
Create an error