I want My::Cache to complain (and refuse to force refreshing) if someone starts modifying the variable without using local.

Um, no you don't, that sounds like horrible API design :) 

$ perl
use Devel::Peek;
use Scalar::Util qw' refaddr ';
our $snot = 66;
Dump $snot;
warn refaddr \$snot;
local $snot = 77;
Dump $snot;
warn refaddr \$snot;
__END__
SV = IV(0x99acf8) at 0x99acfc
  REFCNT = 1
  FLAGS = (IOK,pIOK)
  IV = 66
10071292 at - line 5.
SV = IV(0x3f8c58) at 0x3f8c5c
  REFCNT = 1
  FLAGS = (IOK,pIOK)
  IV = 77
4164700 at - line 8.

$ perl -le " print 0x3f8c5c
4164700

$ perl -le " print 0x99acfc
10071292

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In reply to Re: Detect a localized variable by Anonymous Monk
in thread Detect a localized variable by Sewi

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