Re^4: Best practices - if any? (our)

Variables declared with our create a package variable and a lexically scoped variable

That suggests any use of our creates two variables. It doesn't. It creates an alias (another name) for the variable - the alias is lexically scoped. And no matter how many times you use our, it doesn't create new variables over and over again - unlike my.

my $foo++;  say $foo;
my $foo++;  say $foo;
our $bar++; say $bar;
our $bar++; say $bar;
__END__
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[download]

It does warn. But even if you put all the lines in different scopes (no warnings then), it's still the same variable when using our:

{my $foo++;  say $foo;}
{my $foo++;  say $foo;}
{our $bar++; say $bar;}
{our $bar++; say $bar;}
__END__
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[download]

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Re^5: Best practices - if any? (our) by shmem (Chancellor) on Feb 22, 2010 at 12:49 UTC
But even if you put all the lines in different scopes (no warnings then), it's still the same variable when using our: ...as long as the alias refers to the same package variable. An our in an inner scope creates a new alias: `our $foo; { our $foo = 'foo'; say $foo; } { package Foo; our $foo = 'bar'; say $foo; } package main; say $foo; package Foo; say $foo; { package Foo; our $foo; say $foo; { package Bar; our $foo = 'quux'; say $foo; } say $foo; } { package Foo; say $foo; } __END__ foo bar foo foo bar quux bar foo` [download]	[reply] [d/l]

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Re^5: Best practices - if any? (our)
by shmem (Chancellor) on Feb 22, 2010 at 12:49 UTC

But even if you put all the lines in different scopes (no warnings then), it's still the same variable when using our:

...as long as the alias refers to the same package variable. An our in an inner scope creates a new alias:

our $foo;
{
  our $foo = 'foo'; say $foo;
}
{
  package Foo;
  our $foo = 'bar'; say $foo;
}
package main; say $foo;
package Foo; say $foo;
{
  package Foo;
  our $foo; say $foo;
  {
    package Bar;
    our $foo = 'quux'; say $foo;
  }
  say $foo;
}
{
  package Foo;
  say $foo;
}
__END__
foo
bar
foo
foo
bar
quux
bar
foo
[download]

[reply]
[d/l]