linqx

Modern fork of the original linq for JavaScript.

linqx keeps the familiar LINQ-style API while adding modern exports, new utility methods, improved TypeScript support, and active maintenance.

Written in pure JavaScript with no runtime dependencies.

Key Differences from linq

1. Named Export Added

The original package only exposed a default export.

linqx also provides:

export { Enumerable };

This makes extensions, wrappers, and custom integrations cleaner and more flexible for typescript.

Example:

// enumerable.extensions.ts
import { Enumerable } from "linqx";

declare module "linqx" {
  namespace Enumerable {
    export function crossJoin<T>(this: Enumerable.IEnumerable<T>): Enumerable.IEnumerable<{ left: T; right: T; }>;
  }
}

Enumerable.prototype.crossJoin = function <T>(this: Enumerable.IEnumerable<T>): Enumerable.IEnumerable<{ left: T; right: T; }> {
  return Enumerable.from(crossJoinIterator(this));

  function* crossJoinIterator(enumerable: Enumerable.IEnumerable<T>): Iterable<{ left: T; right: T; }> {
    for (const item of enumerable) {
      for (const otherItem of enumerable) {
        yield { left: item, right: otherItem };
      }
    }
  }
};

Useful when augmenting prototypes or writing reusable helpers.

2. Additional APIs

linqx adds practical methods not available in the original package.

whereIf(flag, predicate)
page(pageNumber, pageSize)
page({ pageNumber, pageSize })
joinWith(separator)
toMap(keySelector, valueSelector)
chunk(size)
index()
position()
withNeighbors()

Installation

npm install linqx

Usage

ES Modules

import Enumerable from "linqx";

const result = Enumerable
  .range(1, 10)
  .where(x => x % 3 === 0)
  .select(x => x * 10)
  .toArray();

Named Export

import { Enumerable } from "linqx";

const values = Enumerable.from([1, 2, 3]);

TypeScript

import Enumerable from "linqx";

const items: Enumerable.IEnumerable<number> = Enumerable.from([1, 2, 3]);

New API Examples

// whereIf
Enumerable
  .from([1, 2, 3, 4])
  .whereIf(true, x => x > 2)
  .toArray();

// chunk
Enumerable
  .from([1, 2, 3, 4, 5])
  .chunk(2)
  .toArray();
// result: [[1, 2], [3, 4], [5]]

// withNeighbors
for (const { prev, item, next } of Enumerable.from([10, 20, 30]).withNeighbors()) {
}

// position
for (const { index, item, isFirst, isLast } of Enumerable.from(["a", "b", "c"]).position()) {  
}

Migration from linq

Most projects can switch directly:

-import Enumerable from "linq";
+import Enumerable from "linqx";

Repository

https://github.com/huoshan12345/linqx

Credits

Based on the original work by Yoshifumi Kawai and later linq maintainers.

Independent community fork.

License

MIT