The do block defines the logical context of the my declaration. Essentially, we:
  1. define $x
  2. assign the value 49 to it
  3. take a reference
  4. let $x go out of scope
  5. bless the reference
  6. store the reference

Since Perl does not have the concept of an anonymous scalar ref (in contrast to {} and []), your kludge is one way of getting that. The best reason to use it is because it works. The worst reason is that you had to ask the question; it doesn't scan unless you know the trick. Were I to write it, I'd probably go with the more verbose: 

my $variable;
ANON_SCALAR_BLOCK: {
    my $x = 49;
    $variable = bless \$x, 'Rates::Notification';
}

[download]
If you really want to use a do, you could also 
my $variable = do {
        my $x = 49;
        bless \$x, 'Rates::Notification';
    };

[download]
which I think scans better.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: Bless and Do by kennethk
in thread Bless and Do by zeltus

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