hey, So I have this function def update( conn, %{ “expense_id” => id, “name” => _name, ocr => _ocr } = payload ) do ... my ocr field is a map that I’m going to update : when I compiled my code I had : cannot use variable ocr as map key inside a pattern. Map keys in patterns can only …

Is the key for ocr content dynamic or static, e.g. "ocr" or :ocr ? If it is dynamic, you can use is_map_key/2 guard, but I really doubt it because it seems you’re using Phoenix and it’s unlikely to have dynamic field names in general.

ocr has dynamics keys for the moment (I’ll define a struct later for it so it will be static ) And yes I’m using Phoenix. Thank you for your answer

There’s really no way of knowing what that pattern match means at compile time, the options I see is to either use is_map_key as @qhwa mentions, like: def update(conn, %{"expense_id" => id, "name" => _name} = params ) when is_map_key(params, "language") or is_map_key(params, "another_key") do .... …

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amnu3387 June 3, 2020, 11:14am 4

What would be the key that ocr represents?