[Haskell-cafe] Fwd: 'let' keyword optional in do notation?
david.feuer at gmail.com
Wed Aug 8 20:13:18 CEST 2012
Is it really so bad to use an explicit let when you need mutually recursive
On Aug 8, 2012 1:51 PM, "Martijn Schrage" <martijn at oblomov.com> wrote:
> On 08-08-12 19:01, Simon Hengel wrote:
> On Wed, Aug 08, 2012 at 12:22:39PM -0400, David Feuer wrote:
> Changing scoping rules based on whether things are right next to each
> other? No thanks.
> Would expanding each let-less binding to a separate let "feel" more
> sound to you?
> That was actually my first idea, but then two declarations at the same
> level will not be in the same binding group, so
> do x = y
> y = 1
> would not compile. This would create a difference with all the other
> places where bindings may appear.
> However, having scope depend on things being next to each other (or
> rather, not having anything in between) is not new. Template Haskell
> declaration splices already cause separate binding groups for top-level
> declarations. Moreover, the new scope rule only holds for let-less
> bindings. If you use explicit lets nothing changes.
> -- Martijn
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
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