As I said, all the OP's examples use the global $_ but some Perl control structures localize that variable.

The same effect is illustrated here using global $::x...

use warnings;
use strict;

sub abc()
{
    $::x = 'x';
}

foreach $::x (1..2)
{
    print "Before:$::x\n";
    abc();
    print "After:$::x\n";
}

print "\$::x = $::x\n";  # warning for uninitialized value $x (global 
+scope)

abc();
print "\$::x = $::x\n";  # prints $x = x

[download]
perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'

In reply to Re^3: What is the scope of $_? by tobyink
in thread What is the scope of $_? by Anonymous Monk

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