# @(#)$Id: Exception.pm 416 2012-11-07 07:46:46Z pjf $ package File::DataClass::Exception; use strict; use warnings; use version; our $VERSION = qv( sprintf '0.13.%d', q$Rev: 416 $ =~ /\d+/gmx ); use Exception::Class 'File::DataClass::Exception::Base' => { fields => [ qw(args class leader out rv) ] }; use base qw(File::DataClass::Exception::Base); use Carp; use MRO::Compat; use English qw(-no_match_vars); use List::Util qw(first); use Scalar::Util qw(blessed); our $IGNORE = [ __PACKAGE__, q(File::DataClass::IO) ]; sub new { my ($self, @rest) = @_; my $args = @rest < 2 ? { error => $rest[ 0 ] } : { @rest }; __is_one_of_us( $args->{error} ) and return $args->{error}; my ($leader, $line, $package); my $level = 3; $args->{level} ||= 3; do { ($package, $line) = (caller( $level ))[ 0, 2 ]; $leader = "${package}[${line}]: "; $level++; } while ($level < $args->{level} or __is_member( $package, $IGNORE )); delete $args->{level}; $args->{error} .= q(); chomp $args->{error}; $args->{error} .= "\n"; return $self->next::method( args => [], class => __PACKAGE__, error => 'Error unknown', ignore_package => $IGNORE, leader => $leader, out => q(), %{ $args } ); } sub catch { my ($self, $e) = @_; $e ||= $EVAL_ERROR; $e or return; return __is_one_of_us( $e ) ? $e : $self->new( $e ); } sub full_message { my $self = shift; my $text = $self->error or return; # Expand positional parameters of the form [_<n>] 0 > index $text, q([_) and return $self->leader.$text; my @args = @{ $self->args }; push @args, map { q() } 0 .. 10; $text =~ s{ \[ _ (\d+) \] }{$args[ $1 - 1 ]}gmx; return $self->leader.$text; } sub stacktrace { my ($self, $skip) = @_; my ($l_no, @lines, %seen, $subr); for my $frame (reverse $self->trace->frames) { unless ($l_no = $seen{ $frame->package } and $l_no == $frame->line) { $subr and push @lines, join q( ), $subr, 'line', $frame->line; $seen{ $frame->package } = $frame->line; } $subr = $frame->subroutine; } defined $skip or $skip = 1; pop @lines while ($skip--); return wantarray ? reverse @lines : (join "\n", reverse @lines)."\n"; } sub throw { my ($self, @rest) = @_; croak __is_one_of_us( $rest[ 0 ] ) ? $rest[ 0 ] : $self->new( @rest ); } sub throw_on_error { my ($self, @rest) = @_; my $e; $e = $self->catch( @rest ) and $self->throw( $e ); return; } # Private subroutines sub __is_member { my ($candidate, $list) = @_; $candidate or return; return (first { $_ eq $candidate } @{ $list }) ? 1 : 0; } sub __is_one_of_us { return $_[ 0 ] && blessed $_[ 0 ] && $_[ 0 ]->isa( __PACKAGE__ ); } 1; __END__ =pod =head1 Name File::DataClass::Exception - Exception base class =head1 Version 0.13.$Revision: 416 $ =head1 Synopsis use Moose; use Try::Tiny; extend qw(File::DataClass::Schema); sub some_method { my $self = shift; try { this_will_fail } catch { $self->throw( $_ ) }; } =head1 Description An exception class that inherits from a custom subclass of L<Exception::Class> =head1 Subroutines/Methods =head2 new Create an exception object. You probably do not want to call this directly, but indirectly through L</catch> and L</throw> =head2 catch $e = File::DataClass::Exception->catch( $error ); Catches and returns a thrown exception or generates a new exception if I<EVAL_ERROR> has been set =head2 full_message $printable_string = $e->full_message What an instance of this class stringifies to =head2 stacktrace $lines = $e->stacktrace( $num_lines_to_skip ); Return the stack trace. Defaults to skipping one (the first) line of output =head2 throw File::DataClass::Exception->throw( $error ); Create (or re-throw) an exception to be caught by the catch above. If the passed parameter is a reference it is re-thrown. If a single scalar is passed it is taken to be an error message code, a new exception is created with all other parameters taking their default values. If more than one parameter is passed the it is treated as a list and used to instantiate the new exception. The 'error' parameter must be provided in this case =head2 throw_on_error File::DataClass::Exception->throw_on_error $error ); Calls L</catch> and if the was an exception L</throw>s it =head1 Diagnostics None =head1 Configuration and Environment The C<$IGNORE> package variable is list of methods whose presence should be suppressed in the stack trace output =head1 Dependencies =over 3 =item L<Exception::Class> =item L<File::DataClass::Constants> =item L<MRO::Compat> =item L<Scalar::Util> =back =head1 Incompatibilities There are no known incompatibilities in this module =head1 Bugs and Limitations The default ignore package list should be configurable There are no known bugs in this module. Please report problems to the address below. Patches are welcome =head1 Author Peter Flanigan C<< <Support at RoxSoft.co.uk> >> =head1 License and Copyright Copyright (c) 2012 Peter Flanigan. All rights reserved This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See L<perlartistic> This program is distributed in the hope that it will be useful, but WITHOUT WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE =cut # Local Variables: # mode: perl # tab-width: 3 # End: