in reply to Data::FormValidator question

I think it's referring to something like this: 
field_filters => { 
     my_filter => sub { my $value = shift; $value =~ s/foo/bar; return
+ $value; },
 },

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filters => [ sub { my $value = shift; $value =~ s/foo/bar; return $val
+ue; } ],

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You can probably do something like this as well: 
sub some_filter_sub {
  my $value = shift;
  $value =~ s/foo/bar;
  return $value;
}
# field_filters => { 
#     my_filter => \&some_filter_sub, 
# },
 filters => [ my_filter => \&some_filter_sub ],

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Update: corrected my misreading of the question and the docs ...

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