Bug #67207 for XML-Parser: [PATCH] Avoid deprecated use of tied()

Sun Apr 03 19:57:47 2011 sprout [...] cpan.org - Ticket created

CC:	slaven [...] rezic.de
Subject:	[PATCH] Avoid deprecated use of tied()
Date:	Sun, 3 Apr 2011 16:57:33 -0700
To:	bug-XML-Parser [...] rt.cpan.org
From:	Father Chrysostomos <sprout [...] cpan.org>

In Perl 5.14, which is soon to be released, using tied($handle) is deprecated. This is because tied($foo) is supposed to act on $foo as a scalar, without regard to whatever value it might hold. (It will be changed to work this way in 5.16.) An explicit * will avoid the warning: tied(*$handle). Here is a patch to fix this. It requires a little explanation: I was going simply to change tied($arg) to eval { tied(*$arg) }, when I realised that this check is unnecessary as of 5.8.0, in which the tiedness of the handle is attached to the IO thingy itself, not to the glob. Then I also realised that the existing logic for testing for a tied handle is faulty and can’t possibly have worked: If tied($arg) returns true and the scalar $arg is not tied, then it can only be a glob, for which ref($arg) returns an empty string. So the ‘if defined &{"${class}::TIEHANDLE"}’ check looks in the main package for a TIEHANDLE subroutine. The rest of the code expects to call methods on the file handle. I do not believe that is possible in 5.6, so this patch simply removes that elsif().

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Sun Apr 03 21:08:17 2011 $_ = 'spro^^*%*^6ut# [...] &$%*c>#!^!#&!pan.org'; y/a-z.@//cd; print - Correspondence added

On Sun Apr 03 19:57:47 2011, sprout@cpan.org wrote: Show quoted text

> In Perl 5.14, which is soon to be released, using tied($handle) is > deprecated. This is because tied($foo) is supposed to act on $foo > as a scalar, without regard to whatever value it might hold. (It > will be changed to work this way in 5.16.) > > An explicit * will avoid the warning: tied(*$handle). > > Here is a patch to fix this. It requires a little explanation: > > I was going simply to change tied($arg) to eval { tied(*$arg) }, when > I realised that this check is unnecessary as of 5.8.0, in which the > tiedness of the handle is attached to the IO thingy itself, not to > the glob. > > Then I also realised that the existing logic for testing for a tied > handle is faulty and can’t possibly have worked: If tied($arg) > returns true and the scalar $arg is not tied, then it can only be a > glob, for which ref($arg) returns an empty string. So the ‘if > defined &{"${class}::TIEHANDLE"}’ check looks in the main package > for a TIEHANDLE subroutine. The rest of the code expects to call > methods on the file handle. I do not believe that is possible in > 5.6, so this patch simply removes that elsif().

I was mistaken. It is possible to call a method on a typeglob, as in *foo->bar. So this better patch makes tied handles work in 5.6 and skips the special handling in 5.8 and higher, as it is unnecessary. I added a local *@, because of the new eval{}, which rendered the existing undef $@ unnecessary. I used defined tied $arg, because the object implementing the tied could have boolean overloading that returns false (paranoid, I know).

Subject:

open_Au0OLhOi.txt

diff -rup XML-Parser-2.40-lsjPau-orig/Expat/Expat.pm XML-Parser-2.40-lsjPau/Expat/Expat.pm --- XML-Parser-2.40-lsjPau-orig/Expat/Expat.pm 2010-09-15 14:44:18.000000000 -0700 +++ XML-Parser-2.40-lsjPau/Expat/Expat.pm 2011-04-03 18:01:19.000000000 -0700 @@ -442,12 +442,12 @@ sub parse { my $result = 0; if (defined $arg) { + local *@; if (ref($arg) and UNIVERSAL::isa($arg, 'IO::Handle')) { $ioref = $arg; - } elsif (tied($arg)) { - my $class = ref($arg); - no strict 'refs'; - $ioref = $arg if defined &{"${class}::TIEHANDLE"}; + } elsif ($] < 5.008 and defined tied($arg)) { + require IO::Handle; + $ioref = $arg; } else { require IO::Handle; @@ -455,20 +455,21 @@ sub parse { no strict 'refs'; $ioref = *{$arg}{IO} if defined *{$arg}; }; - undef $@; } } if (defined($ioref)) { my $delim = $self->{Stream_Delimiter}; my $prev_rs; + my $ioclass = ref $ioref; + $ioclass = "IO::Handle" if !length $ioclass; - $prev_rs = ref($ioref)->input_record_separator("\n$delim\n") + $prev_rs = $ioclass->input_record_separator("\n$delim\n") if defined($delim); $result = ParseStream($parser, $ioref, $delim); - ref($ioref)->input_record_separator($prev_rs) + $ioclass->input_record_separator($prev_rs) if defined($delim); } else { $result = ParseString($parser, $arg);

Sun Apr 03 21:08:18 2011 The RT System itself - Status changed from 'new' to 'open'

Tue May 24 23:48:56 2011 TODDR [...] cpan.org - Correspondence added

RT-Send-CC:

slaven [...] rezic.de

I'm working on a release. This patch has been applied on github: https://github.com/toddr/XML-Parser

Tue May 24 23:48:57 2011 TODDR [...] cpan.org - Status changed from 'open' to 'patched'

Fri Jun 03 00:21:59 2011 TODDR [...] cpan.org - Severity Important added

Fri Jun 03 00:21:59 2011 TODDR [...] cpan.org - Fixed in 2.40_01 added

Fri Jun 03 00:22:13 2011 TODDR [...] cpan.org - Status changed from 'patched' to 'resolved'