The check would be done only once
My tests show otherwise:
#!/usr/bin/perl use warnings; use strict; use feature qw{ say }; use Syntax::Construct qw{ // }; { package Array::Nonempty; use Tie::Array; use parent -norequire => 'Tie::StdArray'; use Carp; sub CLEAR { my $self = shift; $self->[0] = []; } sub TIEARRAY { my ($class, $untie) = @_; bless [ [], $untie ], $class } sub EXTEND { my ($self, $size) = @_; croak "Cannot be empty" if 0 == @{ $self->[0] } && 0 == $size; $self->SUPER::EXTEND($size); # Prevent "untie attempted while 1 inner references still exis +t" my $untie = $self->[1]; undef $self; untie @$untie; } } { package UNIVERSAL; use Attribute::Handlers autotieref => { Nonempty => 'Array::Nonemp +ty' }; } my @list = 1 .. 5; for (1 .. 10) { my @check :Nonempty = @list; shift @list; say tied(@check) // 'not tied'; say "@check"; }
Wrong I was, young padawan. ;-)
There are ways how not to be wrong.
($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord }map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

In reply to Re^5: Declaring with my, assigning, and testing in same line (attributes) by choroba
in thread Declaring with my, assigning, and testing in same line by mordibity

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