For example:

#!/usr/bin/perl

use strict;

sub outer_function {
  my ($v1, $v2) = @_;
  print STDERR "Outer \$v1: " . \$v1 . " = $v1\n";
  return inner_function($v1) . ", $v2";

  sub inner_function {
    print STDERR "Inner \$v1: " . \$v1 . " = $v1\n";
    return $v1;
  }
}

print "First call: " . outer_function("A", "B") . "\n";
print "Secnd call: " . outer_function("X", "Y") . "\n";
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I was expecting the (standard) output to be:

First call: A, B
Secnd call: X, Y
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But instead I get:

Outer $v1: SCALAR(0xa0078a8) = A
Inner $v1: SCALAR(0xa0078a8) = A
First call: A, B
Outer $v1: SCALAR(0x9fee760) = X
Inner $v1: SCALAR(0xa0078a8) = A
Secnd call: A, Y
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