NAME

Devel::Confess - Warns and dies noisily with stack backtraces

SYNOPSIS

  use Devel::Confess;

makes every warn() and die() complains loudly in the calling package and elsewhere. Works even when exception objects are thrown. More often used on the command line:

  perl -MDevel::Confess script.pl

or as shorthand:

  perl -d:Confess script.pl

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), it includes stack traces even when exception objects are thrown.

Here are how stack backtraces produced by this module looks:

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

In the implementation, the Carp module does the heavy work, through longmess(). The actual implementation sets the signal hooks $SIG{__WARN__} and $SIG{__DIE__} to emit the stack backtraces.

Oh, by the way, carp and croak when requiring/using the Carp module are also made verbose, behaving like cluck and confess, respectively.

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

METHODS

import( @options )

Enables stack traces and sets options. Options can be prefixed with no_ to 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. Disabled by default.

color

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

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::Buildin 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, part of the code, and most of the 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

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

BUGS

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

• This module does not play well with other modules which fusses around with warn, die, $SIG{'__WARN__'}, $SIG{'__DIE__'}.

AUTHORS

• Graham Knop, <haarg@haarg.org>

• Adriano Ferreira, <ferreira@cpan.org>

CONTRIBUTORS

None yet.

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/.

cpanm Devel::Confess

perl -MCPAN -e shell
install Devel::Confess