bvaughn

This API was removed in React 17

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Interaction tracing with React

React recently introduced an experimental profiler API. After discussing this API with several teams at Facebook, one common piece of feedback was that the performance information would be more useful if it could be associated with the events that caused the application to render (e.g. button click, XHR response). Tracing these events (or "interactions") would enable more powerful tooling to be built around the timing information, capable of answering questions like "What caused this really slow commit?" or "How long does it typically take for this interaction to update the DOM?".

With version 16.4.3, React added experimental support for this tracing by way of a new NPM package, scheduler. However the public API for this package is not yet finalized and will likely change with upcoming minor releases, so it should be used with caution.

gaearon

Note:

When this guide is more complete, the plan is to move it into Prepack documentation.
For now I put it out as a gist to gather initial feedback.

A Gentle Introduction to Prepack (Part 1)

If you're building JavaScript apps, you might already be familiar with some tools that compile JavaScript code to equivalent JavaScript code:

• Babel lets you use newer JavaScript language features, and outputs equivalent code that targets older JavaScript engines.

rauschma

Strings

String.prototype.*

None of the string methods modify this – they always return fresh strings.

• charAt(pos: number): string ^ES1

  Returns the character at index pos, as a string (JavaScript does not have a datatype for characters). str[i] is equivalent to str.charAt(i) and more concise (caveat: may not work on old engines).

rauchg

Minimum Viable Async with Node 6

With the release of Node 6.0.0, the surface of code that needs transpilation to use ES6 features has been reduced very dramatically.

This is what my current workflow looks like to set up a minimalistic and fast microservice using micro and async + await.

The promise

rauchg

require-from-twitter

Since Twitter doesn't have an edit button, it's a suitable host for JavaScript modules.

How to use

Source tweet: https://twitter.com/rauchg/status/712799807073419264

const leftPad = await requireFromTwitter('712799807073419264');

getify

// please comment if you know of other BOOKS (not considering blogs just yet) on ES6 that are out or coming out

• Understanding ECMAScript 6 -- Nicholas Zakas
• Exploring ES6 -- Axel Rauschmayer
• YDKJS: ES6 & Beyond -- Kyle Simpson
• JS.next: A Manager's Guide -- Aaron Frost
• Expert JavaScript -- Mark E. Daggett
• JavaScript Allongé, The "Six" Edition -- Reginald Braithwaite
• Learning ECMAScript 6 -- Narayan Prusty

ericelliott

Essential JavaScript Links

I no longer mantain this list. There are lots of other very comprehensive JavaScript link lists out there. Please see those, instead (Google "awesome JavaScript" for a start).

addyosmani

CSS Layout Debugger

A tweet-sized debugger for visualizing your CSS layouts. Outlines every DOM element on your page a random (valid) CSS hex color.

One-line version to paste in your DevTools

Use $$ if your browser aliases it:

~ 108 byte version

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

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This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

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CMCDragonkai

AngularJS Directive Attribute Binding Explanation

When using directives, you often need to pass parameters to the directive. This can be done in several ways. The first 3 can be used whether scope is true or false. This is still a WIP, so validate for yourself.

1. Raw Attribute Strings

   <div my-directive="some string" another-param="another string"></div>