Perl exception-handling: choosing eval Try::Tiny core try/catch

You're adding error handling to fresh Perl production code and discover the landscape is split between legacy eval/die patterns, lightweight CPAN modules, and a core syntax that arrived experimental in 5.34 and stable in 5.40. The choice locks you into stringly errors, unnecessary dependencies, or fragile upgrade paths.

Decision at a glance

If your minimum supported Perl is 5.40, the stable core try/catch with finally is the default choice. On 5.34-5.39, Syntax::Keyword::Try provides real-block semantics without waiting for a version bump. When CPAN dependencies are off-limits or the floor is older, Try::Tiny offers a small, pure-Perl safety net. Reserve raw eval/die for tiny scripts or legacy patches where a full redesign isn't warranted.

Option comparison

Trade-offs

• Version gating: enabling feature 'try' in a file that also imports Try::Tiny makes the bareword try ambiguous; pick one mechanism per file.
• $@ clobbering: always copy $@ immediately after eval; destructors run during unwinding and can overwrite it before you inspect it.
• Module maintenance: check MetaCPAN and CPAN Testers before standardizing on a module; release status changes over time.
• Mixing mechanisms: avoid mixing try from core and Try::Tiny in the same namespace to prevent ambiguity.

Concrete pattern: helper with catch, rethrow, and cleanup

# Perl 5.34+ core try/catch example (no CPAN dependency)
use feature 'try';
use strict;
use warnings;

sub risky { die 'disk error'; }

sub safe_process {
    my $result;
    try {
        $result = risky();
    } catch ($e) {
        my $err = $e;
        if ($err eq 'disk error') {
            die Exception->new(message => $err, code => 'DISK');
        }
        die $err;
    }
    return $result;
}

package Exception;
sub new { my ($class, %opts) = @_; bless \%opts, $class; }
sub message { $_[0]{message} // ''; }
sub code    { $_[0]{code}    // undef; }
1;

Verification checklist

1. Run perl -V (or print $]) on the target host to confirm the minimum supported Perl version.
2. Read the perldelta for your exact release (e.g., perldelta perl5.40.0) to confirm try/catch and finally status.
3. Compile syntax: perl -c script.pl. Expected: syntax OK.
4. Run a unit test asserting type and message. Using Test2::Tools::Exception:

   use Test2::Tools::Exception;
   my $e = dies { safe_process(); };
   ok($e->message eq 'disk error', 'exception message matches');
   ok($e->code eq 'DISK', 'exception code set');
   

5. Smoke run: execute the script and verify that cleanup code (in a finally block or END block) runs on failure.

Limitations

• Core try/catch and finally support changed across Perl 5.34-5.40; confirm against the perldelta of the exact Perl you deploy.
• Enabling feature 'try' in a file that also imports Try::Tiny can make the bareword try ambiguous; pick one mechanism per file.
• Always copy $@ immediately after eval; destructors run during unwinding and can overwrite it before you inspect it.
• Module maintenance and CPAN release status are time-sensitive; check MetaCPAN and CPAN Testers before standardizing on a module.