Hello esteemed PerlMonks. I want to assign the value of one variable returned from a CGI.pm script, if it exists, to another, e.g.:

if($q->param('product_key_text')){ # if was entered in the text field,
                                    # set it to product_key
  $q->param('product_key')=$q->param('product_key_text');
 }

[download]

But I'm getting this error when text is entered in product_key_text:

Can't modify non-lvalue subrutine call

I gather I'm trying to modify a param that can't be modified; how do I do this? Thanks!

In reply to CGI.pm: Can't modify non-lvalue subroutine call by slugger415

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