String.prototype.between.js

/**
 * Example: 
 * 'hello {{username}}'.between('{{','}}') === 'username'
 */

String.prototype.between_regexp = function between(begin, end) {
  var regexp = new RegExp(begin + '(.+)' + end);
  return this.match(regexp)[1];
}

String.prototype.between_split = function between(head, tail) {
  var chunks = this.split(head);
  if (typeof chunks[1] === 'undefined') return null;
  var middle = chunks[1].split(tail);
  if (typeof middle[1] === 'undefined') return null
  return middle[0];
}

String.prototype.between_slice = function between(begin, end) {
  var left = this.substring(this.indexOf(begin) + begin.length);
  return left.substring(0, left.indexOf(end));
}

console.time('between_regexp')
for (var i=0; i<10000; i++) {
  '#URL\n\
	ID=396\n\
	NAME=JS/UIX - Terminal\n\
	URL=http://masswerk.at/jsuix/\n\
	UNIQUEID=8BDFD6508BD848FABB35F235B2EFD5B6'.between_regexp('NAME=', '\n')
}
console.timeEnd('between_regexp')


console.time('between_split')
for (var i=0; i<10000; i++) {
  '#URL\n\
	ID=396\n\
	NAME=JS/UIX - Terminal\n\
	URL=http://masswerk.at/jsuix/\n\
	UNIQUEID=8BDFD6508BD848FABB35F235B2EFD5B6'.between_split('NAME=', '\n')
}
console.timeEnd('between_split')


console.time('between_slice');
for (var i=0; i<10000; i++) {
  '#URL\n\
	ID=396\n\
	NAME=JS/UIX - Terminal\n\
	URL=http://masswerk.at/jsuix/\n\
	UNIQUEID=8BDFD6508BD848FABB35F235B2EFD5B6'.between_slice('NAME=', '\n')
}
console.timeEnd('between_slice');