Thanks, but this can't be fixed.

The problem is that the design of List::Util first is broken, no result should be an empty list and not undef! At least in list context ! :(

  DB<28> \@x
 => [1, 2, 3, undef, 5, 6, 7, 8, 9, 10]

  DB<29> @a=List::Util::first { !$_ } @x; \@a
 => [undef]

  DB<30> @a=List::Util::first { $_ eq "never" } @x; \@a
 => [undef]

[download]

I wished people would learn the lesson that () is always better then undef for failure in list operations like iterators or filters.

update

grep does it right!

  DB<38> @a=grep { !$_ } @x; \@a
 => [undef]

  DB<39> @a=grep { $_ eq "never" } @x; \@a
 => []

[download]

Cheers Rolf

( addicted to the Perl Programming Language)

In reply to Re^6: Smartmatch alternatives by LanX
in thread Smartmatch alternatives by cavac

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