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Comment by WJW | Hacker News Reader

There are (some) guards available though? You could rewrite your example as:

    case x {
      n if x < 0 -> ...
      n if x > 10 -> ...
      n if x <= 10 -> ...
    }

Guards are a bit limited in that they cannot contain function calls, but that's a problem of the BEAM and not something Gleam could control.

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Ah right, I remember now.

> Guards are a bit limited in that they cannot contain function calls,

I feel like that's not a small sacrifice.

> but that's a problem of the BEAM and not something Gleam could control.

Could Gleam desugar to a case expression like I wrote above?

Guards also eliminate checking for whether a pattern matching is comprehensive. Or do I remember wrong and the language does not check it at all?

You most likely asked an AI for this. They always think there is an `if` keyword in case statements in Gleam. There isn't one, sadly.

EDIT: I am wrong. Apparently there are, but it's a bit of a strange thing where they can only be used as clauses in `if` statements, and without doing any calculations.

There is though?

https://tour.gleam.run/flow-control/guards/

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