linq.js

/*
	linq.js -- a simple LINQ implementation for javascript
	Author: Nate Kohari <nate@enkari.com>
	Copyright (C) 2009 Enkari, Ltd.
	Released under the Apache 2.0 license (http://www.opensource.org/licenses/apache2.0.php)
*/

Array.prototype.all = function(func) {
	var result = true;
	this.iterate(function(item) {
		if (!func(item)) {
			result = false;
			return false;
		}
	});
	return result;
};

Array.prototype.any = function(func) {
	var result = false;
	this.iterate(function(item) {
		if (func(item)) {
			result = true;
			return false;
		}
	});
	return result;
};

Array.prototype.count = function(func) {
	if (!func) return this.length;
	else return this.where(func).length;
};

Array.prototype.distinct = function(func) {
	var result = [];
	var hash = {};
	this.iterate(function(item) {
		if (!hash[item]) {
			result.push(item);
			hash[item] = true;
		}
	});
	return result;
};

Array.prototype.orderby = function(func) {
	var result = [].concat(this);
	result.sort(function(x, y) {
		return func.apply(x, [x]) - func.apply(y, [y]);
	});
	return result;
};

Array.prototype.orderbydescending = function(func) {
	var result = [].concat(this);
	result.sort(function(x, y) {
		return func.apply(y, [y]) - func.apply(x, [x]);
	});
	return result;
};

Array.prototype.select = function(func) {
	var result = [];
	this.iterate(function(item) {
		result.push(func(item));
	});
	return result;
};

Array.prototype.selectmany = function(func) {
	var result = [];
	this.iterate(function(item) {
		result.concat(func(item));
	});
	return result;
};

Array.prototype.where = function(func) {
	var result = [];
	this.iterate(function(item) {
		if (func(item)) result.push(item);
	});
	return result;
};

Array.prototype.iterate = function(func) {
	for (var idx = 0, len = this.length; idx < len; idx++) {
		if (func.apply(this, [this[idx]]) === false)
			break;
	}
};