tushar
How do I pattern match in multi-level nested maps
Suppose this is my map ,
mymap = %{a: "xxx" , b: %{k1: "k1" , k2: "k2" , c: %{k3: "k3", k4: "k4"}}}
When I do this , I get an error ,
** %{a: v1, b: %{k1: v2, k2: v3, c: %{k3: v4, k4: v4}}} = mymap **
** (MatchError) no match of right hand side value: %{a: "xxx", b: %{c: %{k3: "k3", k4: "k4"}, k1: "k1", k2: "k2"}}
(stdlib) erl_eval.erl:453: :erl_eval.expr/5
(iex) lib/iex/evaluator.ex:257: IEx.Evaluator.handle_eval/5
(iex) lib/iex/evaluator.ex:237: IEx.Evaluator.do_eval/3
(iex) lib/iex/evaluator.ex:215: IEx.Evaluator.eval/3
(iex) lib/iex/evaluator.ex:103: IEx.Evaluator.loop/1
(iex) lib/iex/evaluator.ex:27: IEx.Evaluator.init/4
Trending in Questions
I having some trouble figuring out if I have set myself too strict of standards for my production server. Currently I can handle 75% of r...
New
Hello,
I know there is an approach for handling lists that allows for optimized traversal, but I can’t recall the specific method (somet...
New
Documentation
While reading the Scoped Routes section, I noticed that the documentation currently refers to a problem without explainin...
New
Hi everyone,
I am toying with the idea of building a “match maker” for giving personal help to people that wants to start coding.
I sta...
New
So my question is quite simple and i have found no conclusive answer on forum, google or AI.
Should we use :erlang.float for Integer to ...
New
I recently noticed that Elixir’s Logger defaults its primary log level to :debug when no :logger, :level application configuration is pre...
New
I’m new to elixir and just tried to install the elixirLS extension for VScode(ium) and it is throwing some errors that I would like help ...
New
Other Trending Topics
Edit: 2026 May 15 - This post is archived.
Mob is alive!!
Main docs: mob v0.7.11 — Documentation
A bit of explanation for the slightly c...
New
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
I am happy to introduce the very α version of the new programming language compiled to BEAM.
Welcome Cure.
It has literally three kille...
New
Hobbes is a low-level distributed database for the Elixir programming language.
Hobbes provides a simple, safe, and scalable storage lay...
New
Hi everyone!
The first release candidate for the Expert language server project is now available!
We’ve published a press release detai...
New
A little off-topic, but I feel like people here have a good head on their shoulders.
I used to be quite good at making software. Was luc...
New
Categories:
Sub Categories:
Forums
Popular Tags
- #ecto
- #liveview
- #troubleshooting
- #learning-elixir
- #library
- #deployment
- #erlang
- #testing
- #genserver
- #mix
- #absinthe
- #remote-other
- #otp
- #plug
- #how-to-question
- #macros
- #postgres
- #elixirconf
- #channels
- #exunit
- #discussion
- #code-sync
- #podcasts
- #javascript
- #onsite
- #dialyzer
- #docker
- #authentication
- #umbrella
- #full-time-contract
- #podcasts-by-brainlid
- #ecto-query
- #ai
- #elixirconf-us
- #blog-post
- #elixir-ls
- #phoenix_html
- #iex
- #graphql
- #genstage
- #websockets
- #supervisor
- #advent-of-code
- #distillery
- #processes
- #elixirconf-eu
- #api
- #forms
- #metaprogramming
- #hex










Showing Posts 1 to 5- Show Best Posts
- Show All (oldest first)
- Show All (newest first)
NobbZ
You ask here that
:k3and:k4have values that meatch.tushar
Extremely sorry for the typo , if I extend to below
How do I pattern match if there are multiple sub maps within a map ?
mentero
you still didn’t fix the typo. You ask that
k3:andk4:both have the same valuev4but then pass"k3"and"k4as the values. Your pattern is OK, your data simply doesn’t match.patrickdm
Again, like Noobz wrote you need k3 and k4 values to be the same here. You need another variable vX to match k4 values if it has to be distinct from k3’s
tushar
Apologies , it was indeed the typo causing the issue