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ngruhn • yesterday at 7:31 PM • 2 replies • view on HN

I can live with these negatives. What irritates me the most is the lack of if/else or guards or some kind of dedicated case-distinction on booleans. Pattern matching is great but for booleans it can be kinda verbose. E.g.

   case x < 0 {
     True -> ...
     False -> 
       case x > 10 {
          True -> ...
          False -> 
            case x <= 10 {
               True -> ...
               False -> ...
            }
       }
   }

Replies

WJW • yesterday at 7:37 PM

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.
➕ show 2 replies
lpil • yesterday at 9:26 PM

In Gleam we would typically write this code with `use`, which doesn’t introduce nesting.