I am going through some tutorials, and one of the tasks is to create a list of items by taking first two elements of the existing item and appending them to the end of said list. The problem I have is that for some numerical values in the list, I get a strange response returned. The Cos: defmodule…

What you’re seeing are charlists using the ~c sigil . They are the exact data you expected, but printed as text to allow interoperability with erlang, which uses charlists as their default string type: List — Elixir v1.20.2

I suspected that this may be something like that. Is there a way of ‘forcing’ a standard list view in the console? I assume that this will make no difference for the program (ie. I can pass the list to another function and it will work).

The link I posted shows how to configure the inspect protocol that way. IEx.configure can be used to configure iex with custom inspect options. Indeed the application itself doesn’t care. This is just something relevant to printing the data for human consumption.

IEx.configure(inspect: [charlists: :as_lists]) Run this manually inside iex or put it in a file called .iex.exs at the root of your project and it will be ran automatically on iex startup in that directory.

As an aside, I completely forgot this was out here… [image] Elixir Gotchas and Common Issues Wiki Wikis Preamble This Wiki is intended to be a community-maintained (see the Contribution Guidelines if interested) resource of common “gotchas” (unexpected issues)…

Cool, TIL. But this just flips the confusion the other way around, no? Erlang/OTP 25 [erts-13.2.2.7] [source] [64-bit] [smp:20:20] [ds:20:20:10] [async-threads:1] [jit:ns] Interactive Elixir (1.15.7) - press Ctrl+C to exit (type h() ENTER for help) iex(1)> [97, 98, 99] …

[image] arcanemachine: I’m guessing the tradeoff is that one is less likely to find themself surprised when a charlist is represented as a list of integers, compared to the more-common case where a list of integers is rendered as a charlist, which is a very common surprise for beginners. Yes,…

Hey, I’m in no position to complain while I’m standing on the shoulders of giants. But I have not encountered this tip before, and I think it is definitely worth knowing. It’s funny too, because it’s one of those things that’s obvious in retrospect. I’ve used a line like that to temporarily change …

I agree. It’s not obvious. I’d even argue this config should be the default; I really don’t see who would derive an actual tangible value out of seeing some integer lists as charlists.

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List append (++) does not return a list

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dimitarvp October 10, 2024, 8:56am 14

That’s just list still.