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=encoding utf8
=head1 NAME
Module::Generic::Exception - Generic Module Exception Class
=head1 SYNOPSIS
    my $ex = Module::Generic::Exception->new({
        code => 404,
        type => $error_type,
        file => '/home/joe/some/lib/My/Module.pm',
        line => 120,
        message => 'Invalid property provided',
        package => 'My::Module',
        subroutine => 'customer_info',
    });
    print( "Error stack trace: ", $ex->stack_trace, "\n" );
    # or
    $object->customer_orders || die( "Error in file ", $object->error->file, " at line ", $object->error->line, "\n" );
    # or simply:
    $object->customer_orders || die( "Error: ", $object->error, "\n" );
=head1 DESCRIPTION
This is a simple and straightforward exception class you can use or inherit from. The error object can be stringified or compared.
When stringified, it provides the error message along with precise information about where the error occurred and a stack trace.
L<Module::Generic::Exception> objects are created by L<Module::Generic/"error"> method.
=head1 METHODS
=head2 new
It takes either an L<Module::Generic::Exception> object or an hash reference of properties, or a list of arguments that will be concatanated to form the error message. The list of arguments can contain code reference such as reference to sub routines, who will be called and their returned value added to the error message string. For example :
    my $ex = Module::Generic::Exception->new( "Invalid property. Value recieved are: ", sub{ Dumper( $hash ) } );
    # or
    my $ex = Module::Generic::Exception->new( $other_exception_object_for_reuse );
    # This will the I<object> property
    # or
    my #ex = Module::Generic::Exception->new({
        message => "Invalid property.",
        code => 404,
        type => 'customer',
    })
Possible properties that can be specified are :
=over 4
=item I<code>
An error code
=item I<file>
The localtion where the error occurred. This is populated using the L<Devel::StackTrace/"filename">
=item I<line>
The line number in the file where the error occurred.This is populated using the L<Devel::StackTrace/"line">
=item I<message>
The error message. It can be provided as a list of arguments that will be concatenated, or as the I<message> property in an hash reference, or copied from another exception object passed as the sole argument.
=item I<object>
When this is set, such as when another L<Module::Generic::Exception> object is provided as unique argument, then the properties I<message>, I<code>, I<type>, I<retry_after> are copied from it in the new exception object.
=item I<package>
The package name where the error occurred.  This is populated using the L<Devel::StackTrace/"package">
=item I<retry_after>
An optional value to indicate in seconds how long to wait to retry.
=item I<skip_frames>
This is used as a parameter to L<Devel::StackTrace> upon instantiation to instruct how many it should skip to start creating the stack trace.
=item I<subroutine>
The name of the sub routine from which this was called.  This is populated using the L<Devel::StackTrace/"subroutine">
=item I<type>
An optional error type
=back
It returns the exception object.
=head2 as_string
This returns a string representation of the Exception such as :
    Invalid property within package My::Module at line 120 in file /home/john/lib/My/Module.pm
        # then some strack trace here
=head2 caught
    use TryCatch;
    try
    {
        # An error made with Module::Generic::Exception
        die( $object->error );
    }
    catch( $e )
    {
        # If this error is one of ours
        if( Module::Generic::Exception->caught( $e ) )
        {
            # Do something about it
        }
    }
But L<TryCatch> let's you do this:
    try
    {
        die( $object->error );
    }
    catch( Module::Generic::Exception $e )
    {
        # Do something about it
    }
=head2 code
Set or get the error code. It returns the current value.
=head2 file
Set or get the file path where the error originated. It returns the current value.
=head2 line
Set or get the line where the error originated. It returns the current value.
=head2 message
Set or get the error message. It returns the current value.
It takes a string, or a list of strings which will be concatenated.
For example :
    $ex->messsage( "I found some error:", $some_data );
=head2 package
Set or get the class/package name where the error originated. It returns the current value.
=head2 rethrow
This rethrow (i.e. L<perlfunc/"die">) the original error. It must be called with the exception object or else it will return undef.
This is ok :
    $ex->rethrow;
But this is not :
    Module::Generic::Exception->rethrow;
=head2 retry_after
Set or get the number of seconds to way before to retry whatever cause the error. It returns the current value.
=head2 subroutine
Set or get the subroutine where the error originated. It returns the current value.
=head2 throw
Provided with a message string, this will create a new L<Module::Generic::Exception> object and call L<perlfunc/"die"> with it.
=head2 trace
Set or get the L<Devel::StackTrace> object used to provide a full stack trace of the error. It returns the current value.
=head2 type
Set or get the error type. It returns the current value.
=head1 AUTHOR
Jacques Deguest E<lt>F<jack@deguest.jp>E<gt>
=head1 COPYRIGHT & LICENSE
Copyright (c) 2000-2020 DEGUEST Pte. Ltd.
You can use, copy, modify and redistribute this package and associated
files under the same terms as Perl itself.
=cut