defmodule LousyCalculator do @spec add(number, number) :: {number, String.t} def add(x, y), do: {x + y, "You need a calculator to do that?!"} @spec multiply(number, number) :: {number, String.t} def multiply(x, y), do: {x * y, "Jeez, come on!"} end Typespecs reference — Elixir v1…

No, the end is not optional! When you use do, you have to use end, you can use one-line-syntax though, then you have to replace do foo() end with , do: foo. Be aware of the comma and the colon! Also please try to avoid putting screenshots your posts, when copy-pasting the code and linking to the so…

Thanks for your question @muhajirframe . def and defp have two forms: Normal: def my_func(args) do "result" end Inline (note the , and :): def my_func(args), do: "result" When defining multiple function heads, the inline form can make it easier to visually read what arguments are being…

This behaviour is not related to def and defp in any way. It does apply anywhere where you can pass in a do block. defmodule, defmacro, if, or even your own macros and functions. A very similar thing does work for else as well.

Absolutely correct. The original question was specifically asking about def and defp so I just wanted to make things as clear as possible.

Just to elaborate further on what’s already been mentioned: A do/end block is really just a keyword list under the hood, with a do key and some expression as the value. You can read a little more about it here . In other words do x + y end can also be represented as [do: x + y] def and defp a…

https://hexdocs.pm/elixir/master/syntax-reference.html

No, it is not optional. There are 2 ways of writing body of function - as do-block (and then you need to use end) and as keyword list do: foo. do-block is a sugar for another one, but these are separate constructs.

It isn’t optional, but there’s a special syntax in which its not required. i.e. def foo(), do: --some code here–

[image] ethanvaughn: So, the end IS optional? This made me think what tokens are optional in Elixir’ s syntax, and the only thing that I could come up with were: trailing coma at the end of the elements in a list, map, tuple. return values which default to nil. (not a toke though) Anybody …

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Is `end` keyword optional in elixir when using `def`

Questions & Help Questions

iamahmed January 10, 2022, 4:46pm 13

But I guess, I’m right?