CGI.pm: Can param return array ref?

DBX has asked for the wisdom of the Perl Monks concerning the following question:

my $value = $q->param('foo');
[download]

I would like the code above to return a scalar if the value of 'foo' is a scalar and an array ref if it is a multi-valued parameter. Is there a method for this within CGI or do I have to explicitly program the logic?

Comment on CGI.pm: Can param return array ref? Download Code

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(ar0n) Re: CGI.pm: Can param return array ref? by ar0n (Priest) on Jul 13, 2001 at 22:10 UTC
`my $value = @{ [ $q->param('foo') ] } > 1 ? [ $q->param('foo') ] : $q- +>param('foo');` [download] The above snippet creates an array ref and then derefences it, so it can check the number of elements. If it's greater than one, it creates array ref. [ ar0n ]	[reply] [d/l]
(tye)Re: CGI.pm: Can param return array ref? by tye (Sage) on Jul 13, 2001 at 22:20 UTC
`my $value= [ $q->param('foo') ]; $value= $value->[0] if @$value < 2;` [download] also sets $value to undef if no such parameter exists (and, no, it won't generate a warning unless you later try to use $value in a string or number context). - tye (but my friends call me "Tye")	[reply] [d/l]
Re: CGI.pm: Can param return array ref? by gremio (Acolyte) on Jul 13, 2001 at 22:12 UTC
You have to explicitly program the logic, but it's not as simple as you'd like. CGI.pm explicitly returns you either a scalar, or if you ask for it and it's multivalued, then a list. It inherently can't know whether a parameter must be single valued, or just happens to be. What this means to you is that you should likely use @values = param('foo'); and condition on list length of more than one. Better yet, keep track of which parameters should be multivalued, or use a naming convention like Hungarian. All the best, Gremio mail q.gremio..q.@..q.speakeasy..q@.@.q.org.;	[reply]
Re: CGI.pm: Can param return array ref? by DBX (Pilgrim) on Jul 13, 2001 at 22:29 UTC
Thanks - all these responses were helpful and as ugly as the code I came up with 8-)	[reply]