Did you run the code the OP posted? Since at least 5.6.1, the $1 set by the regexp inside the if is no longer in scope outside the if. The following illustrates this clearly. 

'a' =~ /(.)/;

{
   'b' =~ /(.)/;
   print("$1\n");  # b
}

print("$1\n");     # a

[download]

This is documented in perlvar.

In reply to Re^2: ?: and saving backreferences by ikegami
in thread ?: and saving backreferences by throop

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