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var acorn = require('acorn'); // parser
var esrecurse = require('esrecurse'); // walker
var t = require('ast-types').builders; // ast types
var escodegen = require('escodegen'); // generator
/* parse -> walk -> types -> generate */
var ast = acorn.parse('var x = 23 * 576;'); // code -> ast
// traverse ast
@paulirish
paulirish / what-forces-layout.md
Last active April 23, 2026 06:04
What forces layout/reflow. The comprehensive list.

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics
  • elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent
// make a "base" component
const FakeButton = (props) => (
<div
{...props}
style={{
cursor: 'default',
border: '1px solid',
borderRadius: '3px',
...props.style
}}
/**
* Simple userland CPU profiler using v8-profiler
* Usage: require('[path_to]/CpuProfiler').init('datadir')
*
* @module CpuProfiler
* @type {exports}
*/
var fs = require('fs');
var profiler = require('v8-profiler');
@vkostyukov
vkostyukov / statuses.md
Last active January 18, 2026 10:02
HTTP status codes used by world-famous APIs
API Status Codes
[Twitter][tw] 200, 304, 400, 401, 403, 404, 406, 410, 420, 422, 429, 500, 502, 503, 504
[Stripe][stripe] 200, 400, 401, 402, 404, 429, 500, 502, 503, 504
[Github][gh] 200, 400, 422, 301, 302, 304, 307, 401, 403
[Pagerduty][pd] 200, 201, 204, 400, 401, 403, 404, 408, 500
[NewRelic Plugins][nr] 200, 400, 403, 404, 405, 413, 500, 502, 503, 503
[Etsy][etsy] 200, 201, 400, 403, 404, 500, 503
[Dropbox][db] 200, 400, 401, 403, 404, 405, 429, 503, 507
@nottrobin
nottrobin / github-api-create-pull-request-end-to-end.py
Created September 6, 2016 14:30
With Github API v3, create branch, commit a change to a file and open a pull request
#! /usr/bin/env python
from base64 import b64decode
from github import Github
with open('access-token.txt') as token_file:
token = token_file.read().strip()
api = Github(token)
site = api.get_repo('nottrobin/gh-cms-example-site')
@conorhastings
conorhastings / state-component.js
Last active March 30, 2017 20:36
you can enact most of the behavior of redux with a simple component
/* this lacks subscribe behavior or ability to dispatch from outside of component tree but that is generally not neccesary */
class State extends React.Component {
constructor(props) {
super(props);
this.state = YOUR_INITIAL_STATE;
}
reducer = (action, state, props) => {...newState};
/* setState takes an object of new state as first arg or a function of props and state that returns new state
* which we will use here
* we pass dispatch around and use it similarly to redux dispatch