NAME

       Devel::Confess - Include stack traces on all warnings and errors

SYNOPSIS

       Use on the command line:

         # Make every warning and error include a full stack trace
         perl -d:Confess script.pl

         # Also usable as a module
         perl -MDevel::Confess script.pl

         # display warnings in yellow and errors in red
         perl -d:Confess=color script.pl

         # set options by environment
         export DEVEL_CONFESS_OPTIONS='color dump'
         perl -d:Confess script.pl

       Can also be used inside a script:

         use Devel::Confess;

         use Devel::Confess 'color';

         # disable stack traces
         no Devel::Confess;

DESCRIPTION

       This module is meant as a debugging aid. It can be used to make a script complain loudly
       with stack backtraces when "warn()"ing or "die()"ing.  Unlike other similar modules (e.g.
       Carp::Always), stack traces will also be included when exception objects are thrown.

       The stack traces are generated using Carp, and will work for all types of errors.  Carp's
       "carp" and "croak" functions will also be made to include stack traces.

         # it works for explicit die's and warn's
         $ perl -d:Confess -e 'sub f { die "arghh" }; sub g { f }; g'
         arghh at -e line 1.
                 main::f() called at -e line 1
                 main::g() called at -e line 1

         # it works for interpreter-thrown failures
         $ perl -d:Confess -w -e 'sub f { $a = shift; @a = @$a };' \
                                               -e 'sub g { f(undef) }; g'
         Use of uninitialized value $a in array dereference at -e line 1.
                 main::f(undef) called at -e line 2
                 main::g() called at -e line 2

       Internally, this is implemented with $SIG{__WARN__} and $SIG{__DIE__} hooks.

       Stack traces are also included if raw non-object references are thrown.

       This module is compatible with all perl versions back to 5.6.2, without additional
       prerequisites.  It contains workarounds for a number of bugs in the perl interpreter, some
       of which effect comparatively simpler modules, like Carp::Always.

METHODS

   import( @options )
       Enables stack traces and sets options.  A list of options to enable can be passed in.
       Prefixing the options with "no_" will disable them.

       "objects"
           Enable attaching stack traces to exception objects.  Enabled by default.

       "builtin"
           Load the Devel::Confess::Builtin module to use built in stack traces on supported
           exception types.  Disabled by default.

       "dump"
           Dumps the contents of references in arguments in stack trace, instead of only showing
           their stringified version.  Also causes exceptions that are non-object references and
           objects without string overloads to be dumped if being displayed.  Shows up to three
           references deep.  Disabled by default.

       "dump0", "dump1", "dump2", etc
           The same as the dump option, but with a different max depth to dump.  A depth of 0 is
           treated as infinite.

       "color"
           Colorizes error messages in red and warnings in yellow.  Disabled by default.

       "source"
           Includes a snippet of the source for each level of the stack trace. Disabled by
           default.

       "source0", "source1", "source2", etc
           Enables source display, but with a specified number of lines of context to show.
           Context of 0 will show the entire source of the files.

       "evalsource"
           Similar to the source option, but only shows includes source for string evals.  Useful
           for seeing the results of code generation.  Disabled by default.  Overrides the source
           option.

       "evalsource0", "evalsource1", "evalsource2", etc
           Enables eval source display, but with a specified number of lines of context to show.
           Context of 0 will show the entire source of the evals.

       "better_names"
           Use more informative names to string evals and anonymous subs in stack traces.
           Enabled by default.

       "errors"
           Add stack traces to errors.  Enabled by default.

       "warnings"
           Add stack traces to warnings.  Enabled by default.

       The default options can be changed by setting the "DEVEL_CONFESS_OPTIONS" environment
       variable to a space separated list of options.

CONFIGURATION

   %Devel::Confess::NoTrace
       Classes or roles added to this hash will not have stack traces attached to them.  This is
       useful for exception classes that provide their own stack traces, or classes that don't
       cope well with being re-blessed.  If Devel::Confess::Builtin is loaded, it will
       automatically add its supported exception types to this hash.

       Default Entries:

       Throwable::Error
           Provides a stack trace

       Moose::Error::Default
           Provides a stack trace

ACKNOWLEDGMENTS

       The idea and parts of the code and documentation are taken from Carp::Always.

SEE ALSO

       •   Carp::Always

       •   Carp

       •   Acme::JavaTrace and Devel::SimpleTrace

       •   Carp::Always::Color

       •   Carp::Source::Always

       •   Carp::Always::Dump

CAVEATS

       This module uses several ugly tricks to do its work and surely has bugs.

       •   This module uses $SIG{__WARN__} and $SIG{__DIE__} to accomplish its goal, and thus may
           not play well with other modules that try to use these hooks.  Significant effort has
           gone into making this work as well as possible, but global variables like these can
           never be fully encapsulated.

       •   To provide stack traces on exception objects, this module re-blesses the exception
           objects into a generated class.  While it tries to have the smallest effect it can,
           some things cannot be worked around.  In particular, "ref($exception)" will return a
           different value than may be expected.  Any module that relies on the specific return
           value from "ref" like already has bugs though.

SUPPORT

       Please report bugs via CPAN RT <http://rt.cpan.org/NoAuth/Bugs.html?Dist=Devel-Confess>.

AUTHORS

       •   Graham Knop <haarg@haarg.org>

CONTRIBUTORS

       •   Adriano Ferreira <ferreira@cpan.org>

COPYRIGHT

       Copyright (c) 2005-2013 the "AUTHORS" and "CONTRIBUTORS" as listed above.

LICENSE

       This library is free software and may be distributed under the same terms as perl itself.
       See <http://dev.perl.org/licenses/>.