[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: even more loop fan mail



    "Just implementation lossage"?  That would seem to include all
"lossage" other than design lossage.  It seems kind of ridiculous to
compare something against hypothetical features.  (Do you happen to
know how many calls to lsubrs, with one or more args, there are in
macsyma?  It's the same as the number of words of BPS which would be
saved by a tweak in the compiler.)
    The non-open-compiled map buys you little except space.  The
pdp-10 compiler will always open code in spite of the setting of
MAPEX if you are iterating over more than one list or if there are
references in the lambda-expression to variables local to the
containing code.  The ability to trace or redefine such a thing is
thus very undependable and in any event subject to the constraints of
the particular lisp implementation (you need a handle on that name).
    And of course breaking off the function may keep the compiler
 from performing optimizations, if for no other reason than the
constraint imposed by argument/value passing conventions.