1Devel::SimpleTrace(3) User Contributed Perl DocumentationDevel::SimpleTrace(3)
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NAME

6       Devel::SimpleTrace - See where you code warns and dies using stack
7       traces
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VERSION

10       Version 0.08
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SYNOPSIS

13       On the command-line:
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15           perl -wMDevel::SimpleTrace program_with_strange_errors.pl
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17       Inside a module:
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19           use Devel::SimpleTrace;
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DESCRIPTION

22       This module can be used to more easily spot the place where a program
23       or a module generates errors. Its use is extremely simple, reduced to
24       just "use"ing it.
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26       This is achieved by modifying the functions "warn()" and "die()" in
27       order to replace the standard messages by complete stack traces that
28       precisely indicates how and where the error or warning occurred.  Other
29       than this, their use should stay unchanged, even when using "die()"
30       inside "eval()".
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OPTIONS

33       Options can be set at import time using:
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35           perl -wMDevel::SimpleTrace=option1,option2
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37       or
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39           use Devel::SimpleTrace qw(option1 option2);
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41       Available options are:
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43       "showrefs"
44           Using this option will tell "Devel::SimpleTrace" to stringify
45           objects and references passed in argument to "die()". This option
46           is disabled by default in order to leave objects and references
47           untouched.
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EXAMPLE

50       For example, "HTTP::Proxy" 0.14 suffered from strange warnings, and its
51       author Philippe Bruhat had a hard time trying to understand where they
52       could come from.
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54           getsockname() on closed socket Symbol::GEN7 at /System/Library/Perl/darwin/IO/Socket.pm line 186.
55           Use of uninitialized value in numeric ne (!=) at /Library/Perl/HTTP/Daemon.pm line 53.
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57       Hmm.. There's obviously something wrong here, but spotting the right
58       line is not easy.
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60       Re-running the same script, unchanged, by just adding
61       "-MDevel::SimpleTrace" to "perl" arguments produces the following
62       output:
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64           getsockname() on closed socket Symbol::GEN7
65                   at IO::Socket::sockname(/System/Library/Perl/darwin/IO/Socket.pm:186)
66                   at IO::Socket::INET::sockport(/System/Library/Perl/IO/Socket/INET.pm:231)
67                   at HTTP::Daemon::url(/Library/Perl/HTTP/Daemon.pm:52)
68                   at HTTP::Daemon::ClientConn::get_request(/Library/Perl/HTTP/Daemon.pm:139)
69                   at HTTP::Proxy::serve_connections(/Library/Perl/HTTP/Proxy.pm:500)
70                   at HTTP::Proxy::start(/Library/Perl/HTTP/Proxy.pm:392)
71                   at t::Utils::fork_proxy(t/Utils.pm:72)
72                   at main::(t/50standard.t:138)
73           Use of uninitialized value in numeric ne (!=)
74                   at HTTP::Daemon::url(/Library/Perl/HTTP/Daemon.pm:53)
75                   at HTTP::Daemon::ClientConn::get_request(/Library/Perl/HTTP/Daemon.pm:139)
76                   at HTTP::Proxy::serve_connections(/Library/Perl/HTTP/Proxy.pm:500)
77                   at HTTP::Proxy::start(/Library/Perl/HTTP/Proxy.pm:392)
78                   at t::Utils::fork_proxy(t/Utils.pm:72)
79                   at main::(t/50standard.t:138)
80
81       Aha! Much better. Finding the bug is now a trivial task ";-)"
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DIAGNOSTICS

84       Unknown option: %s
85           (W) This warning occurs if you try to set an unknown option.
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CAVEATS

88       This module is currently not compatible with other modules that also
89       work by overriding "die()" and "warn()", like "CGI::Carp".
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AUTHOR

92       Sébastien Aperghis-Tramoni <sebastien@aperghis.net>
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BUGS

95       Please report any bugs or feature requests to
96       "bug-Devel-SimpleTrace@rt.cpan.org", or through the web interface at
97       <https://rt.cpan.org/Public/Dist/Display.html?Name=Devel-SimpleTrace>.
98       I will be notified, and then you'll automatically be notified of
99       progress on your bug as I make changes.
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102       Devel::SimpleTrace is Copyright (C)2004-2011 Sébastien Aperghis-
103       Tramoni.
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105       This program is free software. You can redistribute it and/or modify it
106       under the same terms as Perl itself.
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110perl v5.34.0                      2022-01-21             Devel::SimpleTrace(3)
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