I prefer to use something like:
sub do_something
{
   my $file = shift || 'default';
}

[download]

since this is also conveniently converted to perform an action:
sub do_something
{
   my $file = shift or
     warn "empty parameter\n";
}

[download]

YMMV.

In reply to (ichimunki) Re x 2: on to better coding (no uninitialized values) by ichimunki
in thread on to better coding (no uninitialized values) by melguin

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