Beefy Boxes and Bandwidth Generously Provided by pair Networks
good chemistry is complicated,
and a little bit messy -LW
 
PerlMonks  

Re^2: the try/catch example from "Programming Perl" analyzed

by Arunbear (Parson)
on Aug 19, 2004 at 14:36 UTC ( #384313=note: print w/ replies, xml ) Need Help??


in reply to Re: the try/catch example from "Programming Perl" analyzed
in thread the try/catch example from "Programming Perl" analyzed

Not sure that the nested if is actually needed. This code works with string and object exceptions (on 5.8.3 at least):

use strict; use warnings; package Exception; package IOException; @IOException::ISA = qw(Exception); package OtherException; package YetAnotherException; package main; *isa = \&UNIVERSAL::isa; my @grisly = ( sub { die "AARRGH!\n" }, sub { die bless [], 'Exception' }, sub { die bless [], 'IOException' }, sub { die bless [], 'OtherException' }, sub { die bless [], 'YetAnotherException' }, sub { print "I live\n"; } ); sub do_something_that_could_die { $grisly[0]->(); # or int(rand(@grisly)) } eval { do_something_that_could_die(); }; if(isa($@, 'Exception')) { print ref($@), ' caught'; } elsif(isa($@, 'OtherException')) { print ref($@), ' caught'; } elsif(ref $@) { # handle any other exception object print ref($@), ' caught'; } elsif($@) { # handle non-object exception print $@; }
Update:
replaced $@->isa('package') calls with calls to UNIVERSAL::isa()


Comment on Re^2: the try/catch example from "Programming Perl" analyzed
Select or Download Code
Re^3: the try/catch example from "Programming Perl" analyzed
by gellyfish (Monsignor) on Aug 19, 2004 at 14:43 UTC

    As long as you are sure you are going to get an object. You may want to use the functional UNIVERSAL::isa() if you want to avoid your 'catch' crapping out when something does just a plain die $!

    /J\

      Thanks, it would also have crapped out if $@ was undefined.

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://384313]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others examining the Monastery: (7)
As of 2015-07-02 04:38 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    The top three priorities of my open tasks are (in descending order of likelihood to be worked on) ...









    Results (27 votes), past polls