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]

my $variable = do {
        my $x = 49;
        bless \$x, 'Rates::Notification';
    };
[download]

An interesting thing to note: Data::Dumper uses a form very similar to OP with blessed references.

perl -MData::Dumper -e 'print Dumper bless \((49)[0]), "Rat::Notificat
+ion";'
$VAR1 = bless( do{\(my $o = 49)}, 'Rat::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.

Yes, do on the outside always scans better, its like creating a sub and calling it immediately,  (sub { ... })->(); except prettier :)

> Yes, do on the outside always scans better, its like creating a sub and calling it immediately, (sub { ... })->(); except prettier :)

To avoid misunderstandings: It's similar but not identical!

  DB<106> sub tst { (sub { return 5 })->(); return 10 }

  DB<107> tst()
 => 10

  DB<108> sub tst { do { return 5 }; return 10 }

  DB<109> tst()
 => 5
[download]

Like with map and grep is the block following do not an anonymous sub!

Cheers Rolf

(addicted to the Perl Programming Language)

While the "standard" is to bless hash-refs, there are occasions where blessing array-refs or code-refs or even scalar-refs make much sense.

BUT there is no "literal notation" for scalar-refs (like [...] or sub{...} )!

That's why a do construct is used, to avoid temporary variables¹.

IIRC does TheDamian talk about this in his (recommended!) PBP book.

HTH! :)

update

¹) like

 
$temp_scalar = 5;
my $scalar_ref = \$temp_scalar;
bless $scalar_ref, ...
[download]

my $variable=bless \(local $_=49) ,'Rates::Notification';
[download]

If you are using $_, then the previous recommendations apply, in order to reduce the scope of the local assignment.