@thi.ng/compare v2.3.4

This project is part of the @thi.ng/umbrella monorepo.

• About
  • Status
• Installation
• Dependencies
• Usage examples
• API
  • ICompare support
  • Cluster sort w/ multiple sort keys
• Authors
• License

About

Comparators with optional support for types implementing the @thi.ng/api ICompare interface.

Since v1.2.0 additional higher-order comparators are included, e.g. to reverse the ordering of an existing comparator and allow hierarchical sorting by multiple keys/dimensions, each with their own optional comparator. See examples below.

Status

STABLE - used in production

Search or submit any issues for this package

Installation

yarn add @thi.ng/compare

ES module import:

<script type="module" src="https://cdn.skypack.dev/@thi.ng/compare"></script>

Skypack documentation

For Node.js REPL:

# with flag only for < v16
node --experimental-repl-await

> const compare = await import("@thi.ng/compare");

Package sizes (gzipped, pre-treeshake): ESM: 396 bytes

Dependencies

• @thi.ng/api

Usage examples

Several demos in this repo's /examples directory are using this package.

A selection:

API

Generated API docs

ICompare support

import { ICompare } from "@thi.ng/api";
import { compare } from "@thi.ng/compare";

class Foo implements ICompare<Foo> {

    x: number;

    constructor(x: number) {
        this.x = x;
    }

    compare(o: Foo) {
        return compare(this.x, o.x);
    }
}

compare(new Foo(1), new Foo(2));
// -1

Cluster sort w/ multiple sort keys

Key-based object comparison is supported for 1 - 4 keys / dimensions.

import * as cmp from "@thi.ng/compare";

const src = [
    { id: "charlie", age: 66 },
    { id: "bart", age: 42 },
    { id: "alice", age: 23 },
    { id: "dora", age: 11 },
];

// cluster sort by id -> age (default comparators)
[...src].sort(cmp.compareByKeys2("id", "age"));
// [
//   { id: 'alice', age: 23 },
//   { id: 'bart', age: 42 },
//   { id: 'charlie', age: 66 },
//   { id: 'dora', age: 11 }
// ]

// cluster sort by age -> id (default comparators)
[...src].sort(cmp.compareByKeys2("age", "id"));
// [
//   { id: 'dora', age: 11 },
//   { id: 'alice', age: 23 },
//   { id: 'bart', age: 42 },
//   { id: 'charlie', age: 66 }
// ]

// cluster sort by age -> id
// (custom comparator for `age` key)
[...src].sort(cmp.compareByKeys2("age", "id", cmp.compareNumDesc));
// [
//   { id: 'charlie', age: 66 },
//   { id: 'bart', age: 42 },
//   { id: 'alice', age: 23 },
//   { id: 'dora', age: 11 }
// ]

// using `reverse()` comparator for `id`
[...src].sort(cmp.compareByKeys2("age", "id", cmp.compare, cmp.reverse(cmp.compare)));
// [
//   { id: 'dora', age: 11 },
//   { id: 'alice', age: 23 },
//   { id: 'bart', age: 42 },
//   { id: 'charlie', age: 66 }
// ]

Authors

Karsten Schmidt

If this project contributes to an academic publication, please cite it as:

@misc{thing-compare,
  title = "@thi.ng/compare",
  author = "Karsten Schmidt",
  note = "https://thi.ng/compare",
  year = 2016
}

License

© 2016 - 2021 Karsten Schmidt // Apache Software License 2.0