Secondly

> ( grep { !exists( $a[$_] ) } keys @a ) ? "can" : "didn\x27t" );

Looks like keys @array was added to Perl in 5.12

And it's obviously inconsistent to delete and exists .

> The very existence of this inconsistency is reason enough for a warning.

But it's even worse!!!

keys is inconsistent to the behavior in hashes, even without using delete and exists and ever seeing any warnings !!!

my (@y,%y);

$y[3]=$y{3}=1;

say "keys \%y: ", join ",",keys %y;
say "keys \@y: ", join ",",keys @y;

[download]

-->

keys %y: 3
keys @y: 0,1,2,3

[download]

A consistent implementation of keys ARRAY should check with exists first before returning an index.

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

In reply to Re^6: Using exists to check element in array by LanX
in thread Using exists to check element in array by david

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