Arunbear has asked for the wisdom of the Perl Monks concerning the following question:

Hello friends,

is there a way to configure Exception::Class so that Perl will show the full stracktrace without myself having to first catch the exception and then call the trace method?

i.e. I want $my_execpt->throw('error_msg') to have the same effect as confess('error_msg')

I need this behaviour because there are times when I want to raise an exception (e.g. subroutine called without a required parameter) but don't want to write a handler for it - and I still need the stracktrace.


Thanks for any assistance.

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Re: Strack traces with Exception::Class
by hardburn (Abbot) on Nov 03, 2003 at 17:24 UTC

    I think it will work if use the Carp module and import verbose, e.g.:

    use Carp 'verbose';

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      I've now tried using Carp with the verbose option, but it does not make Exception::Class's throw method give the strack trace.
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Re: Strack traces with Exception::Class
by IlyaM (Parson) on Nov 04, 2003 at 10:24 UTC

    From Exception::Class documentation:

           * Trace($boolean)
           Each "Exception::Class::Base" subclass can be set
           individually to include a a stracktrace when the
           "as_string" method is called.  The default is to not
           include a stacktrace.  Calling this method with a
           value changes this behavior.  It always returns the
           current value (after any change is applied).

           This value is inherited by any subclasses.  However,
           if this value is set for a subclass, it will there-
           after be independent of the value in "Excep-
           tion::Class::Base".

           This is a class method, not an object method.

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    I.e if you need stacktraces for exception class MyException (and its childs) you need to add

    MyException->Trace(1);

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    Alternatively you can just redefine as_string() method to print uncaught exceptions as you wish.

    --
    Ilya Martynov, ilya@iponweb.net
    CTO IPonWEB (UK) Ltd
    Quality Perl Programming and Unix Support UK managed @ offshore prices - http://www.iponweb.net
    Personal website - http://martynov.org

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      Hopefully, this isn't too old to post to.

      I just had to solve this problem myself. I wanted all exceptions to show stack traces all the time. Since Trace($boolean) is a class method, I just did this (see below) once, and it worked for all child/sub classes and their objects. 

      Exception::Class::Base->Trace(1);

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      I put that right after my use statement.

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