note
tobyink
<p>I suppose it's also worth mentioning that <c>my</c> and <c>our</c> have two other friends: <c>local</c> and <c>state</c>.</p>
<p><c>local</c> sets a new, temporary value for a package variable, which expires at the end of the current scope, with the variable's original value being restored.</p>
<p>In this example, <c>bar()</c> sets <c>$::hello</c> temporarily to <c>"Goodbye"</c> and this new value is visible to <c>foo()</c>, but after <c>bar()</c> has finished running, the original value of <c>"Hello"</c> is restored again.</p>
<code>
use v5.14;
sub foo
{
say $::hello;
}
sub bar
{
local $::hello = "Goodbye";
foo();
}
$::hello = "Hello";
bar();
say $::hello;
</code>
<p>And <c>state</c> can be used to create a variable which keeps its state, not being re-initialised.</p>
<code>
use v5.14;
sub counter {
state $count = 1;
say $count++;
}
counter();
counter();
counter();
counter();
</code>
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<tt>perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'
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