Hi rhesa, Thank you for posting this. I'm using your code in my app with two efficiency tweaks/changes:
  1. check for the 'setting a param' case first
  2. use utf8::decode() instead of decode_utf8(), since due to a bug in Encode, decode_utf8() always sets the UTF8 flag, even for ASCII-only text. utf8::decode() doesn't set the UTF8 flag for this case, so the faster ASCII semantics can be used where possible. (Based on ikegami's comment below, maybe I should say "where safe" instead of "where possible"). See Behaviour of Encode::decode_utf8 on ASCII
package CGI::as_utf8;  # add UTF-8 decode capability to CGI.pm
BEGIN {
  use strict;
  use warnings;
  use CGI 3.47;  # earlier versions have a UTF-8 double-decoding bug
  {   no warnings 'redefine';
      my $param_org = \&CGI::param;
      my $might_decode = sub {
          my $p = shift;
          # make sure upload() filehandles are not modified
          return $p if !$p || ( ref $p && fileno($p) );
          utf8::decode($p);  # may fail, but only logs an error
          $p
      };
      *CGI::param = sub {
          # setting a param goes through the original interface
          goto &$param_org if scalar @_ != 2;
          my $q = $_[0];    # assume object calls always
          my $p = $_[1];
          return wantarray
              ? map { $might_decode->($_) } $q->$param_org($p)
              : $might_decode->( $q->$param_org($p) );
      }
  }
}

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In reply to Re^2: CGI::Application - Which is the proper way of handling and outputting utf8 by mrajcok
in thread CGI::Application - Which is the proper way of handling and outputting utf8 by isync

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