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Re^3: If any element-in-array comparision

by repellent (Priest)
on Jan 29, 2012 at 22:39 UTC ( #950669=note: print w/replies, xml ) Need Help??

in reply to Re^2: If any element-in-array comparision
in thread If any element-in-array comparision

    This will not work:

    print "@a\n" if List::Util::first { 0 == $_ } @a

When using first as a condition, it's best to wrap it in a defined() to specifically check for the 'not found' case:
# this always works print "@a\n" if defined(List::Util::first { defined($_) && 0 == $_ } @ +a);

OTOH, I agree that first clobbers the predicate when checking for undef -- i.e. we can't tell if we found undef:
# doesn't work print "@a\n" if defined(List::Util::first { !defined($_) } @a);

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