Wich one is the best way to reset a variable?

1st method: 
foreach $foo(@foo)
{
  undef $bar;
  ...
  $bar = $some + $thing;
}

[download]
2nd method: 
foreach $foo(@foo)
{
  $bar = 0;
  ...
  $bar = $some + $thing;
}

[download]
TIA, DaWolf

Originally posted as a Categorized Question.

In reply to undef vs. $foo = 0 by DaWolf

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