Not quite.

do_something_with( $item );
will always be the same as
do_something_with( undef );
in your code. foreach restores the initial value when the loops exits (in effect), as seen in the following snippet:

use strict;
my @values = (1, 2, 3, 'a', 4);
my $item = 'z';
foreach $item (@values) {
    last if $item =~ /[^\d]/;
}
print($item);  # Prints 'z', not 'a'.
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I thought it might be using a localized global when my is omitted, but it's clearly not the case:

use strict;

sub test {
   our $item;
   print("[$item]");
}

{
   my @values = (1, 2, 3, 'a', 4);
   my $item = 'z';
   foreach $item (@values) {
      test();
      last if $item =~ /[^\d]/;
   }
   print($item);
}

# Outputs "[][][][]z"

# Changing "my $item" to "our $item"
# changes the output to "[1][2][3][a]z"
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This is perl, v5.6.1 built for MSWin32-x86-multi-thread
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