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Binding the same variable twice in a single form
Let's say I have a function FUNC that returns three values. In a
particular situation I need only the third value. On the
Symbolics I could write
(MULTIPLE-VALUE-BIND (IGNORE IGNORE X) (FUNC)
<use X somehow>)
The question is whether this usage is portable. Other Common Lisp
implementations may treat IGNORE as an ordinary variable name, and
thereby interpret the expression as binding the same variable
twice in the same form. The Symbolics allows this silently in any
case, even an obvious one like
(LET ((A 3) (A 4)) A)
But do other CL implementations act similarly? Does the upcoming
ANSI standard address this question?
Lawrence G. Mayka
AT&T Bell Laboratories
lgm@ihlpf.att.com
Standard disclaimer.