silverdr

silverdr

The documentation says:

Keys in maps can be accessed through some of the functions in this module (such as Map.get/3 or Map.fetch/2) or through the map[] syntax provided by the Access module

Are there any pros/cons for using one over another? I mean especially in situations where the result would be the same. Also any performance / resource usage implications of using one over another?

Showing Posts 1 to 6

sergio

sergio

fetch/2will give you an error and say HEY THIS DOES NOT EXIST. Do something about it!

Map.fetch(medical_kit, :insulin_shot)
:error # CALL 911!

Map.get/2 is more chill and will be like hey uh I couldn’t find anything here’s nil - or give you a default. Like asking your wife for your Tom Ford sunglasses and honey if you can’t find it just grab me my Raybans no big deal.

Map.get(dresser, :tom_ford_sunglasses, :raybans)

10
Post #1
BartOtten

BartOtten

Additionally, the Access syntax is also supported by Keyword List; so it allows for switching between Map en Keyword List without replacing calls.

silverdr

silverdr OP

I updated the question a bit to make it more explicit about what I ask about. I know the different usage possibilities. It is more about when I have a map and want to access existing/non-existing keys (without supplying own default to override the normally returned nil). IOW situations where Map.get and Access behave seemingly the same.

cmo

cmo

map_or_kw[:something] || ”bananas" is Map.get/Keyword.get and is easier on the eye, imo.

Access lets you do nested gets, like map[:one][:two][:three]

gregvaughn

gregvaughn

Related fun fact:

iex(18)> nil[:access_works_for_nil]
nil
marcandre

marcandre

Except map_or_kw[:something] || ”bananas" will behave differently on %{something: false} for example.

— All posts loaded —

Where Next? Top

Trending in Questions Top

stjefim
Hello! Suppose you are building workflow (order / task / payment) processing system with the following requirements: Each workflow con...
New
jonnycharles
I’m in search of an Elixir library that offers PDF generation capabilities similar to Ruby’s Prawn. While there have been discussions abo...
New
spammy
I’m looking to build a personal workflow to quickly deploy web applications written in elixir/phoenix, for local consumption (ie not on t...
New
dli
Before I dive in myself, did anyone successfully sprinkle Hologram into their existing LiveView app? Looking for hints regarding: Addi...
New
roeland
Kia ora, We have been using elixir-google-api to connect to Google Drive. However, with the updates to Tesla due to CVEs this is now bro...
New
bottlenecked
Hi all, I wanted to ask how the community is dealing with post-release steps. Today we have Ecto migrations, which make sure that the db...
New
rahultumpala
Hello, I have an Elixir backend that implements a custom protocol over TCP. I want to load test the backend and assess the performance o...
New

Other Trending Topics Top

JesseHerrick
Hey, I’m Jesse and I’m the main contributor behind Dexter, a full-featured, lightning-fast Elixir LSP optimized for large codebases. It s...
New
jimsynz
Beam Bots (or just BB for short) is a framework for building fault-tolerant robotics applications in Elixir using familiar OTP patterns. ...
New
mcass19
ExRatatui lets you cook up rich terminal UIs in Elixir, powered by Rust’s ratatui via Rustler NIFs. Build interactive terminal applicatio...
New
Damirados
Hello everyone. After busy few months I am happy to announce v0.1.0 of Emerge & Solve. They are GUI (Emerge) and State management (S...
New
netoum
Corex is an accessible, unstyled UI component library for Phoenix that integrates Zag.js state machines using Vanilla JavaScript and Live...
New
ausimian
Emily is an Elixir library that runs Nx computations on Apple’s MLX. Install it as the default Nx backend and Nx, defn, Axon, Nx.Serving,...
New

We're in Beta

About us Mission Statement

Options

Thread Display Mode




Thread Preview

Skip Thread Previews