ljharb

Array Iteration

https://gist.github.com/ljharb/58faf1cfcb4e6808f74aae4ef7944cff

While attempting to explain JavaScript's reduce method on arrays, conceptually, I came up with the following - hopefully it's helpful; happy to tweak it if anyone has suggestions.

Intro

JavaScript Arrays have lots of built in methods on their prototype. Some of them mutate - ie, they change the underlying array in-place. Luckily, most of them do not - they instead return an entirely distinct array. Since arrays are conceptually a contiguous list of items, it helps code clarity and maintainability a lot to be able to operate on them in a "functional" way. (I'll also insist on referring to an array as a "list" - although in some languages, List is a native data type, in JS and this post, I'm referring to the concept. Everywhere I use the word "list" you can assume I'm talking about a JS Array) This means, to perform a single operation on the list as a whole ("atomically"), and to return a new list - thus making it mu

Rich-Harris

Edit — February 2019

This gist had a far larger impact than I imagined it would, and apparently people are still finding it, so a quick update:

• TC39 is currently moving forward with a slightly different version of TLA, referred to as 'variant B', in which a module with TLA doesn't block sibling execution. This vastly reduces the danger of parallelizable work happening in serial and thereby delaying startup, which was the concern that motivated me to write this gist
• In the wild, we're seeing (async main(){...}()) as a substitute for TLA. This completely eliminates the blocking problem (yay!) but it's less powerful, and harder to statically analyse (boo). In other words the lack of TLA is causing real problems
• Therefore, a version of TLA that solves the original issue is a valuable addition to the language, and I'm in full support of the current proposal, which you can read here.

I'll leave the rest of this document unedited, for archaeological

markerikson

import React from "react";
import ReactDOM from "react-dom";

import configureStore from "./store/configureStore";


const store = configureStore();


const rootEl = document.getElementById("root");

TSMMark

git fetch --all -p; git branch -vv | grep ": gone]" | awk '{ print $1 }' | xargs -r -n 1 git branch -D

jaredatron

# Monkey Patch Knapsack to merge reports instead of overwrite
begin
  class Knapsack::Report
    alias_method :save_without_leading_existing_report, :save
    def save
      Knapsack::Presenter.existing_report = open
      save_without_leading_existing_report
    end
  end

dannyvassallo

#  Customize BASH PS1 prompt to show current GIT repository and branch.
#  by Mike Stewart - http://MediaDoneRight.com

#  SETUP CONSTANTS
#  Bunch-o-predefined colors.  Makes reading code easier than escape sequences.
#  I don't remember where I found this.  o_O

# Reset
Color_Off="\[\033[0m\]"       # Text Reset

stevepeak

namespace :codecov do
  desc 'Uploads the latest simplecov result set to codecov.io'
  task upload: :environment do
    require 'simplecov'
    require 'codecov'

    formatter = SimpleCov::Formatter::Codecov.new
    formatter.format(SimpleCov::ResultMerger.merged_result)
  end
end

carcinocron

// Run this in the F12 javascript console in chrome
// if a redirect happens, the page will pause
// this helps because chrome's network tab's
// "preserve log" seems to technically preserve the log
// but you can't actually LOOK at it...
// also the "replay xhr" feature does not work after reload
// even if you "preserve log".

window.addEventListener("beforeunload", function() { debugger; }, false)

hubertlepicki

# I am pasting that into setup steps
# binary provided by the amazing Codeship.io support
PHANTOMJS_URL="https://s3.amazonaws.com/codeship.io/checkbot/binaries/phantomjs_2.0.1"
set -e
rm -rf ~/.phantomjs
wget --continue "${PHANTOMJS_URL}" -O "${HOME}/cache/phantomjs"
ln -s "${HOME}/cache/phantomjs" "${HOME}/bin/"
chmod +x "${HOME}/bin/phantomjs"

Fishrock123

var gulp = require('gulp')

var browserify = require('browserify')
var watchify = require('watchify')
var babelify = require('babelify')

var source = require('vinyl-source-stream')
var buffer = require('vinyl-buffer')
var merge = require('utils-merge')