Common Lisp the Language, 2nd Edition
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Exits
Common Lisp provides a number of iteration constructs. The
loop
construct provides a trivial iteration facility; it is
little more than a progn
with a branch from the bottom back
to the top. The do
and do*
constructs provide
a general iteration facility for controlling the variation of several
variables on each cycle. For specialized iterations over the elements of
a list or n consecutive integers, dolist
and
dotimes
are provided. The tagbody
construct is
the most general, permitting arbitrary go
statements within
it. (The traditional prog
construct is a synthesis of
tagbody
, block
, and let
.) Most of
the iteration constructs permit statically defined non-local exits (see
return-from
and return
).
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