A.Sloman@uk.ac.bham.cs wrote:
: > The missing category of contant-lexical
: > variables is sorely missed in Pop11. (N.B. lconstant is
: > an entirely different concept, despite the name.)
: yes. Something like "lprotect" ?
: Also I seem to recall, from discussions with Rob Duncan about 6 or seven
: years ago that we decided there was a need for a type 4 lexical, for
: optimising things like ML. But I can't now remember what that was.
The same thing: a lexical binding that can't be updated. Closures in
Poplog ML are more costly than they need to be because they're allowing
for the captured variables being updated, even though that's impossible
in SML. So something at the VM level would help enormously there, but
I'd like to see it in Pop-11 too.
Robert
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Robert Duncan, Integral Solutions Ltd. email: robd@isl.co.uk
School of Cognitive & Computing Sciences tel: 01273 678881
University of Sussex, Brighton, BN1 9QH, UK fax: 01273 671320
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