neuecc / Linq.js
Programming Languages
linq.js
LINQ for JavaScript.
Info
Archive, import from Codeplex.
I recommend use fork version - mihaifm/linq
Features
- implement all .NET 4.0 methods and many extra methods (inspired from Rx, Haskell, Ruby, etc...)
- complete lazy evaluation
- full IntelliSense support for VisualStudio
- two versions - linq.js and jquery.linq.js (jQuery plugin)
- support Windows Script Host
- binding for Reactive Extensions for JavaScript(RxJS) and IntelliSense Generator -> see [documentation]
- NuGet install support - linq.js, linq.js-jQuery, linq.js-Bindings
90 Methods
Aggregate, All, Alternate, Any, Average, BufferWithCount, CascadeBreadthFirst, CascadeDepthFirst, Catch, Choice, Concat, Contains, Count, Cycle, DefaultIfEmpty, Distinct, Do, ElementAt, ElementAtOrDefault, Empty, Except, Finally, First, FirstOrDefault, Flatten, ForEach, Force, From, Generate, GetEnumerator, GroupBy, GroupJoin, IndexOf, Insert, Intersect, Join, Last, LastIndexOf, LastOrDefault, Let, Matches, Max, MaxBy, MemoizeAll, Min, MinBy, OfType, OrderBy, OrderByDescending, Pairwise, PartitionBy, Range, RangeDown, RangeTo, Repeat, RepeatWithFinalize, Return, Reverse, Scan, Select, SelectMany, SequenceEqual, Share, Shuffle, Single, SingleOrDefault, Skip, SkipWhile, Sum, Take, TakeExceptLast, TakeFromLast, TakeWhile, ThenBy, ThenByDescending, ToArray, ToDictionary, ToInfinity,ToJSON, ToLookup, ToNegativeInfinity, ToObject, ToString, Trace, Unfold, Union, Where, Write, WriteLine, Zip
- see details - linq.js Reference & LINQPad
Starting linq.js ver.3.0.0-beta!(2012/07/19)
Get v3 branch or NuGet Install-Package linq.js -Pre, linq.js-jQuery -Pre, linq.js-RxJS -Pre, linq.js-QUnit -Pre
All methods becomes lower-camel-case.
Query objects or json
- sample from http://twitter.com/statuses/public_timeline.json
var jsonArray = [
{ "user": { "id": 100, "screen_name": "d_linq" }, "text": "to objects" },
{ "user": { "id": 130, "screen_name": "c_bill" }, "text": "g" },
{ "user": { "id": 155, "screen_name": "b_mskk" }, "text": "kabushiki kaisha" },
{ "user": { "id": 301, "screen_name": "a_xbox" }, "text": "halo reach" }
]
// ["b_mskk:kabushiki kaisha", "c_bill:g", "d_linq:to objects"]
var queryResult = Enumerable.From(jsonArray)
.Where(function (x) { return x.user.id < 200 })
.OrderBy(function (x) { return x.user.screen_name })
.Select(function (x) { return x.user.screen_name + ':' + x.text })
.ToArray();
// shortcut! string lambda selector
var queryResult2 = Enumerable.From(jsonArray)
.Where("$.user.id < 200")
.OrderBy("$.user.screen_name")
.Select("$.user.screen_name + ':' + $.text")
.ToArray();
High compatibility with C# Linq
// C# LINQ (delegate)
Enumerable.Range(1, 10)
.Where(delegate(int i) { return i % 3 == 0; })
.Select(delegate(int i) { return i * 10; });
// linq.js - anonymous function
Enumerable.Range(1, 10)
.Where(function(i) { return i % 3 == 0; })
.Select(function(i) { return i * 10; });
// C# LINQ (lambda)
Enumerable.Range(1, 10).Where(i => i % 3 == 0).Select(i => i * 10);
// linq.js - lambda expression
Enumerable.Range(1, 10).Where("i => i % 3 == 0").Select("i => i * 10");
// $ is default iterator variable like Scala's "_" or Groovy's "it"
Enumerable.Range(1, 10).Where("$ % 3 == 0").Select("$ * 10");
// "" is shorthand of "x => x" (identity function)
Enumerable.Range(4, 7).Join(Enumerable.Range(8, 5), "", "", "outer,inner=>outer*inner");
// Enumerable.From is wrap from primitive array, string(to charArray), object(to KeyValuePair[]) etc..
var array = [100, 200, 30, 40, 500, 40, 200];
var ex1 = Enumerable.From(array).Distinct().ToArray(); // [100, 200, 30, 40, 500]
var ex2 = Enumerable.From("foobar").ToArray(); // ["f", "o", "o", "b", "a", "r"];
var ex3 = Enumerable.From({foo:10, bar:20}).ToArray(); // [{Key:"foo",Value:10}, {Key:"bar",Value:20}]
// C# - AnonymousType
array.Select((val, i) => new { Value = val, Index = i });
// linq.js - object literal
Enumerable.From(array).Select("val,i=>{Value:val, Index:i}")
jQuery plugin version
// $.Enumerable
$.Enumerable.Range(1, 10).Where("$%2==0").ForEach("alert($)");
// TojQuery - Enumerable to jQuery
$.Enumerable.Range(1, 10)
.Select(function (i) { return $("<option>").text(i)[0] })
.TojQuery()
.appendTo("#select1");
// toEnumerable - jQuery to Enumerable
var sum = $("#select1").children()
.toEnumerable()
.Select("parseInt($.text())")
.Sum(); // 55
IntelliSense vsdoc
with Windows Script Host
// get folder name and file name...
var dir = WScript.CreateObject("Scripting.FileSystemObject").GetFolder("C:\\");
// normally
var itemNames = [];
for (var e = new Enumerator(dir.SubFolders); !e.atEnd(); e.moveNext())
{
itemNames.push(e.item().Name);
}
for (var e = new Enumerator(dir.Files); !e.atEnd(); e.moveNext())
{
itemNames.push(e.item().Name);
}
// linq.js
var itemNames2 = Enumerable.From(dir.SubFolders).Concat(dir.Files).Select("$.Name").ToArray();