The OP gets the error message 'Can't call method "abs" on an undefined value' because reduce hasn't been imported, so isn't called, so perl just calls a block of code with $a being undef.

I was saying that *if* the OP fixed her code so that reduce was actually called, then the original error would go away, but a new error message would appear similar to the one you describe, due to a further bug in her code

Dave.

In reply to Re^3: 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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