[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
fsymeval before arg-eval?
Date: Fri, 23 Jan 87 13:49:53 PST
From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)
For compiled code, the macro/functional decision has been made at compile
time, and the question of order-of-evaluation is a legitimate question.
In fact, most implementations I'm aware of do the "fsymeval" *after* the
agruments computations in compiled code, but do it *before* them in the
interpreted code.
....
As far as I know, only VAX/NIL did the fsymeval in compiled code before
the argument computations. Do you know of any others.
Some Symbolics machines do it before, some do it after. I'm less
familiar with other implementations, but I expect we could find several
examples of each way of doing it.
It sounds like it's going to be difficult to come to a concensus on this
across a wide spectrum of implementations. Since dynamically changing
the global function definition of symbols is not something that Common
Lisp promotes as a standard programming technique, perhaps it's best
just to leave it undefined. Normally when the function being called
is not a constant, FUNCALL would be used.