Difference between my ($foo) & my $foo

[sandy1028]

Difference between my($Files) = @_; and my $Files = @_

[GrandFather]

my($Files) = @_;

List context.

my $Files = @_;

Scalar context.

[ELISHEVA]

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

[Anonymous Monk]

$ perl -MO=Deparse,-p -
my($Files) = @_;
my $FilesR = @_;


^D
(my($Files) = @_);
(my $FilesR = @_);
- syntax OK

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()

[planetscape]

You may wish to read these nodes: Context in Perl

[repellent]

With:


my (undef, $a, undef, $b, @rest, $c) = (1, 2, 3, 4, 5, 6, 7, 8);


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)


But:


my $last = (11, 22, 33, 999); # 999 - because assigning LIST to scalar
+ only picks last item