I have a problem, where i have a macro the calls another function. I want to be able to add optional guards to my macro, and call the nested function with those guards. I have a solution, but i feel like it is verbose and there is something i dont know of. Its the use of case do that feels clunky, a…

Honestly this looks fine to me—it’s nice and explicit. It’s not just the when clause that’s different but payload: unquote(pattern) v payload: unquote(payload). What you have is nice and explicit and I think DRYing it up would probably be more confusing (and hence a great case of “when DRY is too …

Consider the (only semi-public but very stable) :elixir_utils.extract_guards/1 function from Elixir’s compiler. It takes in Macro AST of an expression, and returns a two-tuple of that expression with top-level guards removed, and a list of the guards extracted. Its implementation is similar to yours…

He did not disappoint, but also made me more confident in my resolve :grin: TIL about :elixir_utils.extract_guards which is very cool. But for what it’s worth, in a tense debugging session (or even just coming across it randomly in while trying to understand a system) I would much rather see your …

[image] sodapopcan: Although I see Chris K. is replying and he a notorious committer of macro crimes [ezgif-2296daa4eccd89]

[image] sodapopcan: in a tense debugging session (or even just coming across it randomly in while trying to understand a system) I would much rather see your code I’m inclined to agree if this macro is intended for an application. You control the version of Elixir at all points in time, contr…

Yep, I’m glossing over a lot here, especially since OP’s code is clearly a test assertion. There is absolutely a huge difference in what’s acceptable in library v. application code and I was assuming this was for the latter (even if it is library-esque code within application code).

@christhekeele @sodapopcan this is actually from Phoenix, so it is library code. I wanted to add the functionality as stated in my post for testing.

Adding guard to macro that just calls another function

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christhekeele February 24, 2025, 12:42am 5

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