I've got

sub f {
    ($x,$y)=@_;print$x--while$x>=$y
}
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So that's a hole in 32, although it only works for numbers, so it's not a literal implementation of .. reversed.

broquaint

Update: I may have misunderstood the original question so here's my second (possibly more accurate?) shot

perl -le '$_=ord$/;print$_--while$_'
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Which comes to 26, and satisfies chipmunk's need for ouput :o)

Update 2: I've just noticed my solution is exactly the same aforementioned monk, except I've used $_ instead of $a as my var name (I had hoped to exploit $_ in some way ...). Spooky.