DmitrySoshnikov

@kangax's ES6 quiz, explained

@kangax created a new interesting quiz, this time devoted to ES6 (aka ES2015). I found this quiz very interesting and quite hard (made myself 3 mistakes on first pass).

Here we go with the explanations:

Question 1:

(function(x, f = () => x) {

michaelficarra

function escapeUsing(escaper) {
  return function(literalParts, ...interpolatedParts) {
    let s = literalParts[0];
    for (let [interpolatedPart, literalPart] of zip(interpolatedParts, literalParts.slice(1))) {
      s += escaper(interpolatedPart) + literalPart;
    }
    return s;
  }
}

jcupitt

#!/usr/bin/python

# smartcrop with libvips, based very roughly on
# http://stackoverflow.com/a/1517178/894763

import sys

from gi.repository import Vips

image = Vips.Image.new_from_file(sys.argv[1])

cb372

Category theory jargon cheat sheet

A primer/refresher on the category theory concepts that most commonly crop up in conversations about Scala or FP. (Because it's embarassing when I forget this stuff!)

I'll be assuming Scalaz imports in code samples, and some of the code may be pseudo-Scala.

Functor

A functor is something that supports map.

jcupitt

#!/usr/bin/python

# smartcrop with libvips, based very roughly on
# https://github.com/jwagner/smartcrop.js

import sys

import gi
gi.require_version('Vips', '8.0')
from gi.repository import Vips

DmitrySoshnikov

/**
 * = LL parser =
 *
 * by Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
 * MIT Style license
 *
 * Often one can see manually written LL parsers implemented as
 * recursive descent. Approach in this diff is a classical parse table
 * state machine.
 *

chrismdp

# You don't need Fog in Ruby or some other library to upload to S3 -- shell works perfectly fine
# This is how I upload my new Sol Trader builds (http://soltrader.net)
# Based on a modified script from here: http://tmont.com/blargh/2014/1/uploading-to-s3-in-bash

S3KEY="my aws key"
S3SECRET="my aws secret" # pass these in

function putS3
{
  path=$1

jcupitt

#!/usr/bin/python

import sys
from gi.repository import Vips

N_BINS = 10
BIN_SIZE = 256 / N_BINS

im = Vips.Image.new_from_file(sys.argv[1], access = Vips.Access.SEQUENTIAL)

jkrems

In all the discussions about ES6 one thing is bugging me. I'm picking one random comment here from this io.js issue but it's something that comes up over and over again:

There's sentiment from one group that Node should have full support for Promises. While at the same time another group wants generator syntax support (e.g. var f = yield fs.stat(...)).

People keep putting generators, callbacks, co, thunks, control flow libraries, and promises into one bucket. If you read that list and you think "well, they are all kind of doing the same thing", then this is to you.

max-mapper

Disclaimer: This is an unofficial post by a random person from the community. I am not an official representative of io.js. Want to ask a question? open an issue on the node-forward discussions repo

io.js - what you need to know

• io is a fork of node v0.12 (the next stable version of node.js, currently unreleased)
• io.js will be totally compatible with node.js
• the people who created io.js are node core contributors who have different ideas on how to run the project
• it is not a zero-sum game. many core contributors will help maintain both node.js and io.js