cgrothaus
3 different ways to build a list with conditional elements in Elixir (and what that has to do with application startup)
I wrote a blog post about 3 different ways to build a list with conditional elements in Elixir (and what that has to do with application startup).
Most Liked
Eiji
There are other ways to achieve such results for example using recursive functions.
defmodule Example do
def sample(list) do
List.foldr(list, [], fn
{false, _child_spec}, acc -> acc
{true, child_spec}, acc -> [child_spec | acc]
child_spec, acc -> [child_spec | acc]
end)
end
def sample2([]), do: []
def sample2([{false, _child_spec} | rest]), do: sample2(rest)
def sample2([{true, child_spec} | rest]), do: sample2([child_spec | rest])
def sample2([child_spec | rest]), do: [child_spec | sample2(rest)]
end
input = [:not_tuple, {false, :skip_me}, {true, :no_skip}]
Example.sample(input)
Example.sample2(input)
Helpful resources:
2
Popular Backend topics
Shayne gave this excellent talk the other day on Gleam, so I thought I’d share it.
From my point of view it was really interesting to se...
New
New
Julia is a scientific programming language that is free and open source.1 It is a relatively new language that borrows inspiration from l...
New
Ten years without Elixir.
I never got into Elixir, largely because it looked like Ruby. I was a Rubyist for a good while, spent time and...
New
In a previous post we talked about implementing a simple video chat with WebRTC and Elixir. This update will touch on some of the API cha...
New
I had a bit of a mini-adventure following Sobelow’s advice on adding a CSP to a Phoenix App. If you want to follow along, or want to add ...
New
Django 3.2 is just around the corner and it’s packed with new features. Django versions are usually not that exciting (it’s a good thing!...
New
Have you ever wanted to write a structurally typed function in Rust? Do you spend a lot of time and effort getting your Rust struct s jus...
New
Mark Hoffman, the author of Programming WebAssembly in Rust, is a pretty hilarious lecturer if you like a dry sense of humor.
New
Jason Stiebs shows a couple ways for a LiveView to make it easy for users to click and copy an important value to their clipboard. He sho...
New
Other popular topics
Which, if any, games do you play? On what platform?
I just bought (and completed) Minecraft Dungeons for my Nintendo Switch. Other than ...
New
Do the test and post your score :nerd_face:
:keyboard:
If possible, please add info such as the keyboard you’re using, the layout (Qw...
New
In case anyone else is wondering why Ruby 3 doesn’t show when you do asdf list-all ruby :man_facepalming: do this first:
asdf plugin-upd...
New
Oh just spent so much time on this to discover now that RancherOS is in end of life but Rancher is refusing to mark the Github repo as su...
New
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser.
...
New
Author Spotlight
Mike Riley
@mriley
This month, we turn the spotlight on Mike Riley, author of Portable Python Projects. Mike’s book ...
New
Author Spotlight
Rebecca Skinner
@RebeccaSkinner
Welcome to our latest author spotlight, where we sit down with Rebecca Skinner, auth...
New
Programming Ruby is the most complete book on Ruby, covering both the language itself and the standard library as well as commonly used t...
New
If you’re getting errors like this:
psql: error: connection to server on socket “/tmp/.s.PGSQL.5432” failed: No such file or directory ...
New
Ok, well here are some thoughts and opinions on some of the ergonomic keyboards I have, I guess like mini review of each that I use enoug...
New
Categories:
Sub Categories:
Popular Portals
- /elixir
- /rust
- /wasm
- /ruby
- /erlang
- /phoenix
- /keyboards
- /python
- /js
- /rails
- /security
- /go
- /swift
- /vim
- /clojure
- /emacs
- /java
- /haskell
- /svelte
- /onivim
- /typescript
- /kotlin
- /c-plus-plus
- /crystal
- /tailwind
- /react
- /gleam
- /ocaml
- /elm
- /flutter
- /vscode
- /ash
- /html
- /opensuse
- /zig
- /centos
- /deepseek
- /php
- /scala
- /react-native
- /lisp
- /sublime-text
- /textmate
- /nixos
- /debian
- /agda
- /django
- /deno
- /kubuntu
- /arch-linux
- /nodejs
- /revery
- /ubuntu
- /manjaro
- /spring
- /lua
- /diversity
- /julia
- /markdown
- /v









