I get errors on all the lines using param:

my $writer = param{'writer'};
my $title = param{'title'};
my $text = param{'text'};
my $current = param{'current'};
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Perhaps you'd like to look more closely at the CGI docs, and call the param function (or call the param method on your CGI) instead of passing a hash array reference to param?

my $writer = param('writer')
# or
my $writer = $cgi->param('writer');
# etc.
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Update:Your calls are parsing to this:

my $var = param({'this'});
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So perl is interpreting your argument as a hash array reference with one key and no value.