Number 1 is just weird and number 2 doesn't compile.

Huh? 2 compiles perfectly well for me!

# Doggie.pm
package Doggie;

1;

sub new {
  # ignore args
  print "hello from Doggie::new\n";
}

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use strict;
use warnings;
use Doggie;

sub Doggie {
  print "hello from main::Doggie\n";
}

my $objref1 = Doggie::->new(Tail => 'short', Ears => 'long');
my $objref2 = new Doggie:: Tail => 'short', Ears => 'long';

# The following is parsed as Doggie()->new(...)
# my $objref3 = Doggie->new(Tail => 'short', Ears => 'long');

__END__

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hello from Doggie::new
hello from Doggie::new

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Also, in addition to the use that adrianh cited, 1 would be useful in the rare case in which one wants to use a class that has the same name as a subroutine defined in the client package. In such a case, as the OP has already noted, the parser gets confused with 3.

the lowliest monk

In reply to Re^2: P248 programming perl by tlm
in thread P248 programming perl by wackattack

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