npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

@voxpelli/type-helpers

v3.4.0

Published

My personal type helpers

Downloads

10,589

Readme

@voxpelli/type-helpers

My personal type helpers

npm version npm downloads Follow @voxpelli@mastodon.social

Usage

JSDoc / Types in JS

/** @typedef {import('@voxpelli/type-helpers').PartialKeys} PartialKeys */

TypeScript

import type { PartialKeys } from '@voxpelli/type-helpers';

Declaration types

A mechanism for third-party extendible discriminated unions.

  • AnyDeclaration<Declarations, [DeclarationsExtras={}]> – returns a union of all valid declarations in Declarations
  • AnyDeclarationType<Declarations, [DeclarationsExtras={}]> – returns a union of the type names from all valid declarations in Declarations
  • ValidDeclaration<TypeName, Declarations, [DeclarationsExtras={}]> – the base type of a valid declaration for Declarations / DeclarationsExtras that also validates that TypeName exists as a valid declaration in Declarations

Details on how to use declarations

Valid declarations

  1. Are part of Declarations
  2. Complies with the DeclarationsExtras type
  3. Has a type key that matches a declarations key in Declarations

Declaration types example

Imaginary module @voxpelli/foo:

import type {
  AnyDeclaration,
  AnyDeclarationType,
  ValidDeclaration
} from '@voxpelli/type-helpers';

interface FooDeclarationExtras {
  value: unknown
}

export interface FooDeclarations {
  bar: FooDeclaration<'bar', { abc: 123 }>,
  // This is a recommended addition, ensuring consumers stay alert and are aware
  // that extensions here can be of all kinds of types
  unknown: FooDeclaration<'unknown', unknown>,
}

export type AnyFooDeclaration = AnyDeclaration<FooDeclarations, FooDeclarationExtras>;
export type AnyFooDeclarationType = AnyDeclarationType<FooDeclarations, FooDeclarationExtras>;

export interface FooDeclaration<TypeName extends AnyFooDeclarationType, Value>
  extends ValidDeclaration<TypeName, FooDeclarations, FooDeclarationExtras>
{
  value: Value
}

Third party extension:

import type { FooDeclaration } from '@voxpelli/foo';

declare module '@voxpelli/foo' {
  interface FooDeclarations {
    xyz: FooDeclaration<'xyz', { xyz: true }>
  }
}

Usage as a :

/**
 * @param {AnyFooDeclaration} foo
 */
function timeToFoo (foo) {
  switch (foo.type) {
    case 'bar':
      // foo.value.abc will be know to exist and be a number
      break;
    case 'xyz':
      // If the third party extension has been included, then foo.value.xyz will be know to exist here and be a boolean
      break;
    default:
      // foo.value is eg. unknown here
  }
}

Object types

  • ObjectEntry<T> – a typed equivalent to all invidiual items Object.entries() returns
  • ObjectEntries<T> – an array of ObjectEntry<T>, mmore similar to what Object.entries() returns
  • ObjectFromEntries<T> – a typed equivalent of what Object.fromEntries() returns
  • PartialKeys<Foo, 'abc'> – makes the key abc of Foo optional
  • UnknownObjectEntry – the least specific entry for ObjectFromEntries<T> and what T needs to be a subset of there

String types

  • NonGenericString<T, [ErrorMessage]> – ensures that T is not a generic string (and as such likely a string literal)
  • NonGenericStringArray<T, [ErrorMessage]> – similar to NonGenericString but with T being an Array / ReadonlyArray

Util types

  • Equal<A, B> – if A extends B, then resolves to A, else resolved to never
  • LiteralTypeOf<T> – resolves to a string literal that matches the typeof operator
  • MaybePromised<T> – resolves to T | Promise<T>

Used by

Similar modules

  • type-fest – a large colelction of type helpers