Proposal: Non-recursive let

Jon Fairbairn jon.fairbairn at
Wed Jul 10 10:00:29 CEST 2013

Andreas Abel
<andreas.abel at> writes:

> Proposal: add a non-recursive let to the Haskell language.  In
>   let' p = e in e'
>   do { ... let' p = e ... }
> the variables of pattern p are then *not* in scope in e.
> Reasons for adding a non-recursive let:
> 1. recursive-let is the source for many non-termination bugs.

-1 from me. I don’t see that having non-recursive let available
will have much impact on the bugs. It just changes forgetting to
use different variable names because of recursion (which is
currently uniform throughout the language) to forgetting to use
non recursive let instead of let.
Jón Fairbairn                                 Jon.Fairbairn at

More information about the Haskell-prime mailing list