听说最近 left-pad 很火

[hcy910]

（手动滑稽）

left-pads

Usage

CoffeeScript

leftpad = require './left-pad'

leftpad 'foo', 5
# => "  foo"

leftpad 'foobar', 6
# => "foobar"

leftpad 1, 2, 0
# => "01"

Haskell

module Main where
    import LeftPad

    main :: IO ()
    main = putStrLn $ leftpad "foo" 6 'f'
    -- => ffffoo

Scheme

(load 'left-pad.scm')
(leftpad "foo" 6 #\f) ; => "ffffoo"

PHP

<?php
include_once 'left-pad.php';
echo leftpad("foo", 6, 'f'); // => "ffffoo"
?>

[xuwenmang]

https://pypi.python.org/pypi/left-pad
https://rubygems.org/gems/left-pad
https://www.nuget.org/packages/left-pad/

[loading]

其实这个函数正儿八经是用来做什么的？

[sox]

@loading

const month = new Date().getMonth() + 1

leftPad(month, 2, 0)

[zhujinliang]

@sox 具体到这种情况，我是判断小于 10 的…

[sox]

我估计吐槽 left-pad 的人大部分人不知道 lodash.padStart()

[loading]

@sox 我都是自己写的…也没去找好一点的实现，自己的标准也就是写出能跑的代码…

[Outshine]

http://left-pad.io/

[h0wardc]

"I ’ ve Just Liberated My Modules"
https://medium.com/@azerbike/i-ve-just-liberated-my-modules-9045c06be67c

including "left-pad"
https://gist.githubusercontent.com/azer/db27417ee84b5f34a6ea/raw/50ab7ef26dbde2d4ea52318a3590af78b2a21162/gistfile1.txt

The npm Blog: kik, left-pad, and npm
http://blog.npmjs.org/post/141577284765/kik-left-pad-and-npm

[h0wardc]

"NPM & left-pad: Have We Forgotten How To Program?"
http://www.haneycodes.net/npm-left-pad-have-we-forgotten-how-to-program/

[realpg]

PHP: str_pad

[dphdjy]

一直~
x 位插入字符+目标字符
取后 n 位~
不知道性能怎么样~

[magicdawn]

@sox 3.9 还是 padLeft 来着， 4 成了 padStart

[hcy910]

@realpg 其实这个就是用的这个函数 233

[ryanouyang]

@Outshine 这是什么鬼，还专门写了个 api
http://api.left-pad.io/?str=asdfasdf&len=12&ch=a