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@rosskevin
rosskevin / relay.js
Last active June 27, 2018 01:07
flow libdef for relay modern 1.2. This is in a _works for me_ state. Someone please export these properly from relay or create a proper flow-typed libdef.
// @flow
declare module 'react-relay' {
declare export type RecordState = 'EXISTENT' | 'NONEXISTENT' | 'UNKNOWN';
declare export type onCompleted = (response: ?Object, errors: ?Array<PayloadError>) => void
declare export type onError = (error: Error) => void
declare export type CommitOptions = {
onCompleted: onCompleted,
@ruizb
ruizb / advanced-example.md
Last active September 26, 2023 20:21
Reader monad example using fp-ts

The following section is not part of monet.js documentation, but I think it's worth showing how we can compose readers using fp-ts.

Reader composition

Let's say we have the following piece of code:

interface Dependencies {
  logger: { log: (message: string) => void }
 env: 'development' | 'production'
@OliverJAsh
OliverJAsh / foo.md
Last active September 4, 2023 15:31
`Option` vs non-`Option`

Option vs non-Option

Option<T> non-Option (T | undefined)
accessing property userOption.map(user => user.age) userNullish?.age
calling a method userOption.map(user => user.fn()) userNullish?.fn()
providing fallback ageOption.getOrElse(0) ageNullish ?? 0
filter ageOption.filter(checkIsOddNumber) `ageNull
@slikts
slikts / react-memo-children.md
Last active October 19, 2025 02:45
Why using the `children` prop makes `React.memo()` not work

nelabs.dev

Why using the children prop makes React.memo() not work

I've recently ran into a pitfall of [React.memo()][memo] that seems generally overlooked; skimming over the top results in Google just finds it mentioned in passing in a [React issue][regit], but not in the [FAQ] or API [overview][react-api], and not in the articles that set out to explain React.memo() (at least the ones I looked at). The issue is specifically that nesting children defeats memoization, unless the children are just plain text. To give a simplified code example:

const Memoized = React.memo(({ children }) => (<div>{children}</div>));
// Won't ever re-render
<Memoized>bar</Memoized>
// Will re-render every time; the memoization does nothing
@sindresorhus
sindresorhus / esm-package.md
Last active April 7, 2026 15:43
Pure ESM package

Pure ESM package

The package that linked you here is now pure ESM. It cannot be require()'d from CommonJS.

This means you have the following choices:

  1. Use ESM yourself. (preferred)
    Use import foo from 'foo' instead of const foo = require('foo') to import the package. You also need to put "type": "module" in your package.json and more. Follow the below guide.
  2. If the package is used in an async context, you could use await import(…) from CommonJS instead of require(…).
  3. Stay on the existing version of the package until you can move to ESM.
@gaearon
gaearon / 00-README-NEXT-SPA.md
Last active January 29, 2026 09:20
Next.js SPA example with dynamic client-only routing and static hosting

Next.js client-only SPA example

Made this example to show how to use Next.js router for a 100% SPA (no JS server) app.

You use Next.js router like normally, but don't define getStaticProps and such. Instead you do client-only fetching with swr, react-query, or similar methods.

You can generate HTML fallback for the page if there's something meaningful to show before you "know" the params. (Remember, HTML is static, so it can't respond to dynamic query. But it can be different per route.)

Don't like Next? Here's how to do the same in Gatsby.

@trys
trys / globalTokens.stylex.ts
Created January 17, 2024 21:44
StyleX X Utopia
/**
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
*
*/
import stylex from '@stylexjs/stylex';