If one takes the DBI as an example typically RaiseError is used in conjunction with eval, or a module like Try::Tiny or TryCatch, to catch the exception that's been thrown and handle it.

Let's look at the example that marto gives: (Note he states "Feel free to add error checking etc")

#!/usr/bin/perl
use strict;
use warnings;
use Mojo::UserAgent;

my $url = 'https://en.wikipedia.org/wiki/File:ENIAC-changing_a_tube.jp
+g';

my $ua  = Mojo::UserAgent->new;
my $dom = $ua->get( $url )->res->dom; 
my $target = $dom->at('#file > a:nth-child(1) > img:nth-child(1)')->at
+tr('src');
$ua->get('https:' . $target)->res->save_to('target.jpg') ;

[download]

Is there any way to "raise error" so I can utilize something like a try/catch?

Added:

In the code above the $url (in the first ->get) might be bad; the css selector (used in the ->at) might be invalid for the html returned; the argument to the second ->get could be bad and the ->save_to could fail due to some IO error. Adding checks for all these possibilities would be rather painful.

In reply to Re^2: Error handling in Mojolicious by clueless newbie
in thread Error handling in Mojolicious by clueless newbie

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