function reWhitespace( options ) {
	var opts;
	var err;
	if ( arguments.length > 0 ) {
		opts = {};
		err = validate( opts, options );
		if ( err ) {
			throw err;
		}
		if ( opts.capture ) {
			return new RegExp( '('+REGEXP_STRING+')', opts.flags );
		}
		return new RegExp( REGEXP_STRING, opts.flags );
	}
	return /[\u0009\u000A\u000B\u000C\u000D\u0020\u0085\u00A0\u1680\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u2028\u2029\u202F\u205F\u3000\uFEFF]/; // eslint-disable-line no-control-regex
}
Returns a regular expression to match a white space character.

@param {Options} [options] - function options
@param {string} [options.flags=''] - regular expression flags
@param {boolean} [options.capture=false] - boolean indicating whether to wrap a regular expression matching white space characters with a capture group
@throws {TypeError} options argument must be an object
@throws {TypeError} must provide valid options
@returns {RegExp} regular expression

@example
var RE_WHITESPACE = reWhitespace();

var bool = RE_WHITESPACE.test( ' ' );
// returns true

bool = RE_WHITESPACE.test( '\t' );
// returns true

@example
var replace = require( '@stdlib/string/replace' );
var RE_WHITESPACE = reWhitespace({
    'capture': true
});

var str = 'Duplicate capture';
var out = replace( str, RE_WHITESPACE, '$1$1' );
// returns 'Duplicate  capture'