Juan Pablo Royo Sales jproyo

Rust in a Nutshell

Table of Contents

Rust: The Language
Dependency injection

You'll generally want to look at:

heap
stack
gc profiles

Do not get bogged down in microoptimizations before you've assessed any macro optimizations that are available. IO and the choice of algorithm dominate any low level changes you may make. In the end you have to think hard about your code!

Topos> For example, if i see that a particular pure function is taking a  long time relative to the rest of the code, and that it's Text, and I'm seeing ARR_WORDS rise linearly in the heap, I probably have a thunk-based memory leak. This is knowledge you build up over time.

Tips for Spacemacs with Haskell

C-c C-l => Load ghci in place with the current buffer
<SPC> C-r => Reformat region hindent
, F => Format imports
, f => hindent
, r b => hlint refactor buffer
, r s => suggestions
, r r => refactor at point
, h i => info at point

	module Format.Stdout where

	import Control.Program
	import qualified Data.Map.Strict as M
	import Relude

	output :: Histogram -> IO ()
	output =
	mapM_ (\(k, v) -> putStrLn $ show k ++ " " ++ replicate (fromIntegral v) '#') . M.assocs

	\documentclass{article}
	\usepackage{amsmath}

	\begin{document}

	Five ways to prove $P \implies Q$

	\begin{itemize}
	\item \textbf{Direct Proof}: $P \implies Q$
	\item \textbf{Proof by Contrapositive}: $\neg Q \implies \neg P$

	{-# LANGUAGE TypeOperators #-}
	module HsOpTy where

	import GHC.TypeLits

	-- brittany-disable-next-binding
	type Foo =
	Int :
	'[]

	{-# LANGUAGE TypeApplications #-}
	{-# LANGUAGE OverloadedStrings #-}

	module Test where

	import Data.Aeson
	import Data.ByteString.Lazy as BL
	import Data.Text as T

	data User = User { name :: Text

	# stylish-haskell configuration file
	# ==================================

	# The stylish-haskell tool is mainly configured by specifying steps. These steps
	# are a list, so they have an order, and one specific step may appear more than
	# once (if needed). Each file is processed by these steps in the given order.
	steps:
	# Convert some ASCII sequences to their Unicode equivalents. This is disabled
	# by default.
	# - unicode_syntax:

	#!/bin/bash

	stack install apply-refact hlint stylish-haskell hasktags hoogle intero hindent ispell
	brew install ispell

	{-# LANGUAGE GeneralisedNewtypeDeriving #-}

	module Data where

	type UserName = String

	data DataResult = DataResult String
	deriving (Eq, Show)

	class Monad m => Cache m where