Syntax extensions: mdo and do...rec

Ross Paterson ross at soi.city.ac.uk
Mon Sep 29 17:31:43 EDT 2003


On Mon, Sep 29, 2003 at 07:31:33AM -0700, Levent Erkok wrote:
> > > BTW, in GHC 6.2 with the -fglasgow-exts -farrows flags, you will be able
> > > to use either mdo or do...rec for monads and for arrows, as an experiment.
> > > (Maybe "rec" wasn't such a great keyword to take from the identifier
> > > space.)
> 
> "rec" is nice to have, but I think the "proc" notation also needs a
> corresponding "mproc" to do the automatic segmentation. The end
> programmers need not worry about extra "recs," it just adds another level
> of complexity (just like the let/let rec discussion). Ross: any plans on
> implementing that?

It's in the bit you re-quoted (not "mproc" but "mdo" inside "proc").


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