> Alternatively, of course, the coding style could simply change to
>
> case e of
> -- ...
> _other -> default_action
>
> or
>
> case e of
> -- ...
> _ -> default_action
>
> The former is IMHO ugly, and the latter fails to indicate to the
> reader that this is intended to match not *all* alternatives, but just
> those not already matched.
I like the first one - it makes it clear that you don't intend to use the
identifier. Unfortunately keywords beginning with '_' don't behave like
wildcards - there's nothing stopping you from using this identifier on the
right-hand side, so we just have to adopt this as a convention.
Perhaps when unused identifier warnings are turned on, GHC should also warn
about non-binding occurrences of identifiers beginning with '_'?
Cheers,
Simon
