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I *think* the problem is that Devel::Peek is writing directly to the C file descriptor 2 (see perlfuc:fileno) rather than via a perl file handle, which basicaly means that any attempt to capture its output via tie is simply bypassed. Ie. The tie magic only works when you use the filehandle, which the perl internals don't.

Update: Forget the rest of this, it's bo..er..wrong! It couldn't work.

I have a feeling that it may be possible to capture the output by dupping the file descriptor. POSIX::dup2 might be one way, and re-opening files(dups) using the "&=2" version of the syntax might be another. I have had a play with the latter, without success, but I didn't spend much time on it.


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In reply to Re: Best Way to Redirect STDERR to a Scalar by BrowserUk
in thread Best Way to Redirect STDERR to a Scalar by Mr. Muskrat

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    [hippo]: Understood. I'll have to go through the code and see if it's doing anything fancy with ties, dual-vars or non-scalars. In the end, it's probably a bug though.
    [Corion]: Aaah - you should be able to do this with overload, but I would hit somebody really hard if they constructed objects that are true but the empty string, and you not knowing about the domain knowledge where this makes sense
    [Eily]: you could tie a variable into not having the same value each time, if you like to make people who try to debug your code facepalm
    [Corion]: perl -wle 'package o; use overload q("") => sub {warn "str"; ""}, bool => sub{warn "bool"; 1}; package main; my $o={}; bless $o => o; print "Yay" if ($o && !length($o))'
    [Corion]: But people writing such code should document the objects they construct and why it makes sense for an object to be invisible as string while being true in a boolean context
    [hippo]: That's equal parts clever and horrendous.
    [Eily]: the overload version wouldn't return true with "$x" && !length $x though, I guess
    [hippo]: The more I look at this code, the more $x is a plain old scalar and the more this condition will never be true. I'm calling it a bug at this point.
    [hippo]: Thanks for your input which has soothed my sanity (a little)

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