basarat/required.js

## required.js
/**
 * Called if a parameter is missing and
 * the default value is evaluated.
 */
function mandatory() {
  throw new Error('Missing parameter');
}
function foo(mustBeProvided = mandatory()) {
  return mustBeProvided;
}

## sample.md

      
    Raw
  

              sample.md
            
          
    foo()
Error: Missing parameter
foo(123)
Ok
	/**
	* Called if a parameter is missing and
	* the default value is evaluated.
	*/
	function mandatory() {
	throw new Error('Missing parameter');
	}
	function foo(mustBeProvided = mandatory()) {
	return mustBeProvided;
	}