Difference between my ($foo) & my $foo

sandy1028 has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Difference between my ($foo) & my $foo by GrandFather (Saint) on Feb 12, 2009 at 07:50 UTC
`my($Files) = @_;` [download] List context. `my $Files = @_;` [download] Scalar context. True laziness is hard work	[reply] [d/l] [select]
Re: Difference between my ($foo) & my $foo by ELISHEVA (Prior) on Feb 12, 2009 at 08:52 UTC
Here is a fairly simple explanation of what is meant by list and scalar context: http://www.linuxtopia.org/Perl_Programming/pickingUpPerl_50.html Best, beth	[reply]
Re: Difference between my ($foo) & my $foo by Anonymous Monk on Feb 12, 2009 at 07:50 UTC
`$ perl -MO=Deparse,-p - my($Files) = @_; my $FilesR = @_; ^D (my($Files) = @_); (my $FilesR = @_); - syntax OK` [download] Its list context versus scalar context, example `@_ = 0 .. 3; my( $one, $two, $three ) = @_; print "one($one)two($two)three($three)\n"; ( $one, $two, $three ) = scalar @_; print "one($one)two($two)three($three)\n"; __END__ one(0)two(1)three(2) one(4)two()three()` [download]	[reply] [d/l] [select]
Re: Difference between my ($foo) & my $foo by planetscape (Chancellor) on Feb 14, 2009 at 05:03 UTC
You may wish to read these nodes: Context in Perl HTH, planetscape	[reply]
Re: Difference between my ($foo) & my $foo by repellent (Priest) on Feb 12, 2009 at 19:54 UTC
With: `my (undef, $a, undef, $b, @rest, $c) = (1, 2, 3, 4, 5, 6, 7, 8);` [download] Now: `@rest` will be greedily assigned: `@rest = (5, 6, 7, 8)` the other variables are respectively assigned: `($a, $b, $c) = (2, 4, undef)` Then: `my $count = @rest; # 4 - because there are four items (scalar contex +t) my ($first) = @rest; # 5 - because first item is 5 (list context)` [download] But: `my $last = (11, 22, 33, 999); # 999 - because assigning LIST to scalar + only picks last item` [download]	[reply] [d/l] [select]