PoignardAzur

About variadics in Rust

This is an analysis of how variadic generics could be added to Rust. It's not a proposal so much as a summary of existing work, and a toolbox for creating an eventual proposal.

Introduction

Variadic generics (aka variadic templates, or variadic tuples), are an often-requested feature that would enable traits, functions and data structures to be generic over a variable number of types.

To give a quick example, a Rust function with variadic generics might look like this:

abel0b

apt install flex bison
git clone https://github.com/microsoft/WSL2-Linux-Kernel --depth 1
cd WSL2-Linux-Kernel/tools/perf
make -j8
sudo cp perf /usr/local/bin

ryanatkn

{
  // Commented-out options have their default values.
  "include": ["src/**/*"],
  "exclude": ["node_modules/*"],
  // "files": [], // A list of relative or absolute file paths to include.
  // "extends": "", // A string containing a path to another configuration file to inherit from.
  // "references": [], // An array of objects `{"path": "./to/dirOrConfig"}` that specifies projects to reference.
  // "compileOnSave": false, // Signals to the IDE to generate all files for a given tsconfig.json upon saving.

  "compilerOptions": {

liamosaur

{
  "mode": "patterns",
  "proxySettings": [
    {
      "address": "127.0.0.1",
      "port": 8080,
      "username": "",
      "password": "",
      "type": 1,
      "title": "127.0.0.1:8080",

tclementdev

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

• You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.

• Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse

evanw

// This code demonstrates a simplified "stackification" algorithm to turn
// instructions in a basic block back into a tree. This is useful when
// generating WebAssembly code from assembly instructions in SSA form.
//
// It's the algorithm used by LLVM's WebAssembly backend, viewable here:
// https://github.com/llvm-mirror/llvm/blob/master/lib/Target/WebAssembly/WebAssemblyRegStackify.cpp

type InsKind =
  'Add' |
  'LocalSet' |

spacejam

using rust with rr

rr is a great debugging tool. it records a trace of a program's execution, as well as the results of any syscalls it executes, so that you can "rewind" while you debug, and get deterministic forward and reverse instrumented playback. it works with rust, but by default if you try it out, it could be pretty ugly when you inspect variables. if this bothers you, configure gdb to use a rust pretty-printer

rr is probably in your system's package manager.

usage

jFransham

Achieving warp speed with Rust

Contents:

• Number one optimization tip: don't
• Never optimize blindly
• Don't bother optimizing one-time costs
• Improve your algorithms
• CPU architecture primer
• Keep as much as possible in cache
• Keep as much as possible in registers

KodrAus

Profiling performance

Using perf:

$ perf record -g binary
$ perf script | stackcollapse-perf.pl | rust-unmangle | flamegraph.pl > flame.svg

NOTE: See @GabrielMajeri's comments below about the -g option.

basarat

import * as React from 'react';

interface FormProps {
  /**
   * Automatically prevents the default browser behavior so you don't have to
   */
  onSubmit: () => any;
  children?: JSX.Element;
}
export const Form = ({ onSubmit, children}: FormProps) =>