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

harpocrates

In a recent discussion I had with a friend about Haskell and Scala, they brought up the fact that they sometimes miss Scala's partial functions. In Scala, these are a trait of their own somewhat different from what Haskellers usually understand by "partial function". In particular, you can check if a value is in the domain of the partial function before applying it to the function.

Interestingly enough, partial functions are also supported in Haskell - they just happen to be hidden away in some more obscure parts of the base library. What follows is my attempt to make a module that brings this functionality out and makes it more accessible. Since this is meant to be a literate Haskell source, let's start with some preamble.

{-# LANGUAGE TypeOperators, NoImplicitPrelude, GeneralizedNewtypeDeriving #-}

module Data.Function.Partial where

import Prelude hiding (id, (.), ($))

mbinna

Effective Modern CMake

Getting Started

For a brief user-level introduction to CMake, watch C++ Weekly, Episode 78, Intro to CMake by Jason Turner. LLVM’s CMake Primer provides a good high-level introduction to the CMake syntax. Go read it now.

After that, watch Mathieu Ropert’s CppCon 2017 talk Using Modern CMake Patterns to Enforce a Good Modular Design (slides). It provides a thorough explanation of what modern CMake is and why it is so much better than “old school” CMake. The modular design ideas in this talk are based on the book [Large-Scale C++ Software Design](https://www.amazon.de/Large-Scale-Soft

alswl

[repositories]
  local
  huaweicloud-ivy: https://mirrors.huaweicloud.com/repository/ivy/, [organization]/[module]/(scala_[scalaVersion]/)(sbt_[sbtVersion]/)[revision]/[type]s/[artifact](-[classifier]).[ext]
  huaweicloud-maven: https://mirrors.huaweicloud.com/repository/maven/ 
  bintray-typesafe-ivy: https://dl.bintray.com/typesafe/ivy-releases/, [organization]/[module]/(scala_[scalaVersion]/)(sbt_[sbtVersion]/)[revision]/[type]s/[artifact](-[classifier]).[ext]
  bintray-sbt-plugins: https://dl.bintray.com/sbt/sbt-plugin-releases/, [organization]/[module]/(scala_[scalaVersion]/)(sbt_[sbtVersion]/)[revision]/[type]s/[artifact](-[classifier]).[ext], bootOnly

  # aliyun not works for ivy
  # aliyun-ivy: https://maven.aliyun.com/repository/public/, [organization]/[module]/(scala_[scalaVersion]/)(sbt_[sbtVersion]/)[revision]/[type]s/[artifact](-[classifier]).[ext]
  # aliyun-public-mirror:  https://maven.aliyun.com/repository/public/

MattPD

C++ links: Coroutines

https://github.com/MattPD/cpplinks / C++ Standard / C++20 / Coroutines

(draft; work in progress)

#coroutines (C++ Slack): https://cpplang.slack.com/archives/C5JS5JXT5

Contents

lexi-lambda

Monads and delimited control are very closely related, so it isn’t too hard to understand them in terms of one another. From a monadic point of view, the big idea is that if you have the computation m >>= f, then f is m’s continuation. It’s the function that is called with m’s result to continue execution after m returns.

If you have a long chain of binds, the continuation is just the composition of all of them. So, for example, if you have

m >>= f >>= g >>= h

then the continuation of m is f >=> g >=> h. Likewise, the continuation of m >>= f is g >=> h.