A visual example would probably work wonders. Here's the pattern:
(iflet (<var1> . <rest>) body (iflet (<var2> . <rest>) <rest> (iflet (<var3> . <rest>) <rest> <three-or-more-arg case> <two-arg case>) <one-arg case>) <zero-arg case>)
(delisting <rest> body <zero-arg case> <var1> <one-arg case> <var2> <two-arg case> <var3> <three-or-more-arg case>)
Incidentally, halfway through writing that post with 'delisting and 'aif, the 'aif code read (decomposing body ...). XD
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