Off the top of my head, I can't think of an instance where $a = $b would give a different result than $a = "$b".
This will explode horribly if $b is a reference. Compare the following: 
[ateague@dingbat mod]$ perl -MData::Dumper -E '$b = [qw/1 2 3 4 5/]; $
+a = $b; say Dumper $a;'
$VAR1 = [
          '1',
          '2',
          '3',
          '4',
          '5'
        ];

[ateague@dingbat mod]$ perl -MData::Dumper -E '$b = [qw/1 2 3 4 5/]; $
+a = qq|$b|; say Dumper $a;'
$VAR1 = 'ARRAY(0x12609e4)';

[download]
The first one prints the array referenced by the reference. The second one simply prints a string containing the memory address of the array reference.

In reply to Re^3: Loop Control by ateague
in thread Loop Control by slugman

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