(Two people so far have failed to realise that $a and $b are used by List::Util::reduce in the same way as sort.)

Anyway, your immediate problem is that you don't include reduce in the 'use List::Util' import list. But after fixing that, your next problem is that $a and $b start off as objects, but after the first reduce, $a is now a simple number rather than an object, so $a->abs fails.

Dave.

In reply to Re: Can't call method "abs" on an undefined value. by dave_the_m
in thread Can't call method "abs" on an undefined value. by HollyKing

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