This is a technique that allows common error handling for a block of code to be managed without resorting to error state variables, labeled statements or gotos.

It's most useful where some common error handling code needs to be executed before continuing with normal execution.

Sample code prints one of:

all the way
Do various stuff in the block
Skipped the early exit
Skipped an error detection
Continue here regardless

early exit
Do various stuff in the block
Continue here regardless

found error
Do various stuff in the block
Skipped the early exit
Errors handled here
Continue here regardless

[download]
use warnings;
use strict;

$_ = ('all the way', 'early exit', 'found error')[rand (3)];
print "$_\n";

    {# Block to allow common error handling in continue
        print "Do various stuff in the block\n";
        
        last if /early exit/;
        print "Skipped the early exit\n";
        
        next if /found error/;
        print "Skipped an error detection\n";
        
        last; # Falls through to error handling if omitted
    } continue {
        print "Errors handled here\n";
    }
    
print "Continue here regardless\n";

[download]

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