function repeat( str, n ) {
	if ( !isString( str ) ) {
		throw new TypeError( format( 'invalid argument. First argument must be a string. Value: `%s`.', str ) );
	}
	if ( !isNonNegativeInteger( n ) ) {
		throw new TypeError( format( 'invalid argument. Second argument must be a nonnegative integer. Value: `%s`.', n ) );
	}
	return base( str, n );
}
Repeats a string a specified number of times and returns the concatenated result.

@param {string} str - string to repeat
@param {NonNegativeInteger} n - number of times to repeat the string
@throws {TypeError} first argument must be a string
@throws {TypeError} second argument must be a nonnegative integer
@throws {RangeError} output string length must not exceed maximum allowed string length
@returns {string} repeated string

@example
var str = repeat( 'a', 5 );
// returns 'aaaaa'

@example
var str = repeat( '', 100 );
// returns ''

@example
var str = repeat( 'beep', 0 );
// returns ''