[Haskell-cafe] Prolog-style patterns
roma at ro-che.info
Tue Apr 9 14:20:40 CEST 2013
* Daniel Trstenjak <daniel.trstenjak at gmail.com> [2013-04-09 13:01:07+0200]
> Hi Roman,
> > In fact, lots of Haskell newcomers are surprised that
> > f 10 = 42
> > is not the same as
> > n = 10
> > f n = 42
> Well, yes, at the beginning I've been also surprised about this.
> But allowing this seems to be even more error prone, because now you
> could "bind" function arguments to values by just importing a module.
Oh, don't get me wrong — I'd never actually suggest that semantics.
Just saying that allowing one and not other would confuse the newcomers
about how pattern matching actually works. So I prefer to stay on the
simple and consistent side.
More information about the Haskell-Cafe