function mapFunAsync( n, done ) {
		if ( !isNonNegativeInteger( n ) ) {
			throw new TypeError( format( 'invalid argument. Number of function invocations must be a nonnegative integer. Value: `%s`.', n ) );
		}
		if ( !isFunction( done ) ) {
			throw new TypeError( format( 'invalid argument. Last argument must be a function. Value: `%s`.', done ) );
		}
		return limit( n, opts, f, clbk );

		/**
		* Callback invoked upon completion.
		*
		* @private
		* @param {(Error|null)} error - error object
		* @param {Array} results - results
		* @returns {void}
		*/
		function clbk( error, results ) {
			if ( error ) {
				return done( error );
			}
			done( null, results );
		}
	}
Invokes a function `n` times and returns an array of accumulated function return values.

@private
@param {NonNegativeInteger} n - number of function invocations
@param {Callback} done - function to invoke upon completion
@throws {TypeError} first argument must be a nonnegative integer
@throws {TypeError} last argument must be a function
@returns {void}