invalidVariableName function

bool invalidVariableName(String keyword, { bool strictMode = true, })

Returns true for invalid JS variable names, such as keywords. Also handles invalid variable names in strict mode, like "arguments".

Implementation

bool invalidVariableName(String keyword, {bool strictMode = true}) {
  switch (keyword) {
    // http://www.ecma-international.org/ecma-262/6.0/#sec-future-reserved-words
    case 'await':
    case 'break':
    case 'case':
    case 'catch':
    case 'class':
    case 'const':
    case 'continue':
    case 'debugger':
    case 'default':
    case 'delete':
    case 'do':
    case 'else':
    case 'enum':
    case 'export':
    case 'extends':
    case 'finally':
    case 'for':
    case 'function':
    case 'if':
    case 'import':
    case 'in':
    case 'instanceof':
    case 'let':
    case 'new':
    case 'return':
    case 'super':
    case 'switch':
    case 'this':
    case 'throw':
    case 'try':
    case 'typeof':
    case 'var':
    case 'void':
    case 'while':
    case 'with':
      return true;
    case 'arguments':
    case 'eval':
    // http://www.ecma-international.org/ecma-262/6.0/#sec-future-reserved-words
    // http://www.ecma-international.org/ecma-262/6.0/#sec-identifiers-static-semantics-early-errors
    case 'implements':
    case 'interface':
    case 'package':
    case 'private':
    case 'protected':
    case 'public':
    case 'static':
    case 'yield':
      return strictMode;
  }
  return false;
}