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@ClickerMonkey
ClickerMonkey / types.ts
Last active August 8, 2024 00:25
Typescript Helper Types
// when T is any|unknown, Y is returned, otherwise N
type IsAnyUnknown<T, Y, N> = unknown extends T ? Y : N;
// when T is never, Y is returned, otherwise N
type IsNever<T, Y = true, N = false> = [T] extends [never] ? Y : N;
// when T is a tuple, Y is returned, otherwise N
// valid tuples = [string], [string, boolean],
// invalid tuples = [], string[], (string | number)[]
@schettino
schettino / useUserReducer.ts
Created March 30, 2019 20:23
Better Reducers with React and Typescript 3.4
import { useReducer } from 'react'
export function updateName(name: string) {
return <const>{
type: 'UPDATE_NAME',
name
}
}
export function addPoints(points: number) {
@gaearon
gaearon / prepack-gentle-intro-1.md
Last active March 22, 2025 07:22
A Gentle Introduction to Prepack, Part 1

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.
@clarkbw
clarkbw / redux-performance-mark.js
Last active February 8, 2024 05:03
A User Timing middleware for redux to create performance markers for dispatched actions
const timing = store => next => action => {
performance.mark(`${action.type}_start`);
let result = next(action);
performance.mark(`${action.type}_end`);
performance.measure(
`${action.type}`,
`${action.type}_start`,
`${action.type}_end`
);
return result;
@myshov
myshov / function_invocation.js
Last active August 19, 2024 12:23
11 Ways to Invoke a Function
console.log(1);
(_ => console.log(2))();
eval('console.log(3);');
console.log.call(null, 4);
console.log.apply(null, [5]);
new Function('console.log(6)')();
Reflect.apply(console.log, null, [7])
Reflect.construct(function(){console.log(8)}, []);
Function.prototype.apply.call(console.log, null, [9]);
Function.prototype.call.call(console.log, null, 10);
@bbengfort
bbengfort / venv_cheat_sheet.md
Created August 20, 2014 14:16
My virtualenv and virtualenv wrapper cheat sheet. I alias the commands of virtualenv and virtualenv wrapper for my own development environment.

Ben's VirtualEnv Cheatsheet

This cheat sheet describes my usage/implementation of virtualenv with virtualenv wrapper and the bash foo that I added with the help of many blogs to make it all tick together in fun land.

Quick Reference

$ echo $WORKON_HOME
/Users/benjamin/.virtualenvs

$ echo $PROJECT_HOME
@staltz
staltz / introrx.md
Last active May 4, 2025 15:01
The introduction to Reactive Programming you've been missing
@erans
erans / get_lat_lon_exif_pil.py
Created May 20, 2011 21:16
Get Latitude and Longitude from EXIF using PIL
from PIL import Image
from PIL.ExifTags import TAGS, GPSTAGS
def get_exif_data(image):
"""Returns a dictionary from the exif data of an PIL Image item. Also converts the GPS Tags"""
exif_data = {}
info = image._getexif()
if info:
for tag, value in info.items():
decoded = TAGS.get(tag, tag)