array slice?

zeltus has asked for the wisdom of the Perl Monks concerning the following question:

I think my question is to do with array slices... but of course, I may be wrong!

my @tarray = qw(one two three four five);
my ($v2) = @tarray;
my $v3 = (@tarray)[0];
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Now, I am used to extracting slices using

my $v3 = (@tarray)[0];
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in this case, extract the first element from @tarray and "give" it to $v3...but upon examining some legacy code, I came across...

my ($v2) = @tarray;
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...which does the same thing. But I can't work out why it works. Can someone please explain? Is it classifiable as a form or array slicing? I prefer my way for clarity, but are there any pros and cons for either method?

Thank you!

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Re: array slice?
by Athanasius (Archbishop) on Jan 31, 2014 at 15:32 UTC

Hello zeltus,

I think you have already answered your own main question. But your preferred syntax:

my $v3 = (@tarray)[0];
[download]

looks a little odd. At the least, it’s unnecessarily complex: it says, “Take the elements of @tarray; treat them as a list; and return the first element of that list.” More straightforward to cut out the middle step and just say:

my $v3 = $tarray[0];
[download]

If you do need a slice, an array slice is also more straightforward here than a list slice:

my ($v4, $v5) = @tarray[0, 2];
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