[plt-scheme] Does anyone use `set!' and `get!' patterns?
No, I don't think so -- get and set patterns aren't just that. They
bind mutators and gettors to some place down inside some value. Sam
isn't proposing to get rid of the ML-like dereferencing ref cells.
Robby
On Sun, Mar 9, 2008 at 8:46 AM, Joe Wells <jbw at macs.hw.ac.uk> wrote:
> "Sam TH" <samth at ccs.neu.edu> writes:
>
> > Currently, "plt-match.ss" and scheme/match (in v4) provide `set!' and
> > `get!' patterns, which bind mutators and accessors for the matched
> > locations, respectively. While these look clever, they complicated the
> > implementation of match, and don't seem to be used. In particular,
> > I've searched the entire collections hierarchy, and they don't seem to
> > be used at all. Given this, I'd like to remove the implementations.
> > Does anyone else use them in their code, or have any reason that they
> > would want to?
>
> ML has this feature in pattern matching (in SML a pattern like "ref x"
> dereferences a mutable cell and binds its current contents to x). So
> presumably PLT can claim to implement a superset of ML pattern
> matching. Without this feature, ML fanboys could say "but you don't
> have mutator patterns, so our language is better, ha ha ha".
>
> --
> Joe
>
>
> _________________________________________________
> For list-related administrative tasks:
> http://list.cs.brown.edu/mailman/listinfo/plt-scheme
>