That works until you have a parameter where "0" is a valid value. 

my @param_names = $q->param();
my %present_params;
@present_params{ @param_names } = (1) x @param_names;

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The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re^3: Form Validation Ideas by Fletch
in thread Form Validation Ideas by Trihedralguy

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