Uh, not quite. It's because it's a failed match. Apparently, the block that localizes the match variables doesn't begin until after the open curlies (and does not include the boolean expression of the if). Check this: 
$_ = "abcde";
if (/(.)(.)/) { # first two
  if (/(.)(.)$/) { # last two, by your theory won't upset
    print "inner: $1 $2\n";
  }
  # by your theory, should see first two again
  print "outer: $1 $2\n";
}

[download]
for which I get 
inner: d e
outer: d e

[download]
But if you add a block: 
$_ = "abcde";
if (/(.)(.)/) { # first two
  { # ADDED
  if (/(.)(.)$/) { # last two, by your theory won't upset
    print "inner: $1 $2\n";
  }
  } # ADDED
  # by your theory, should see first two again
  print "outer: $1 $2\n";
}

[download]
we do in fact get the expected: 
inner: d e
outer: a b

[download]

-- Randal L. Schwartz, Perl hacker

In reply to RE: Re: Scope of regular expression variables by merlyn
in thread Scope of regular expression variables by FauxPasIII

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