I am trying to create a hash of references for use in a factory-methodish subroutine. My idea is as follows: 
my %constructors = ( "one" => \One->new,
                     "two" => \Two->new );

sub factorish {
    my ( $type, @arguments ) = @_;

    my $consref = $constructors{ $type }
        or die "No handler for $type.";

    return $consref -> ( @arguments );
}

[download]

This does not compile, from the obvious reason that I don't have references in the hash. The reason I don't want to use

my %constructors = ( "one" => \&One::new,
                     "two" => \&Two::new );

[download]

is that I will then have to explicitly fournish the package name in the factorish function, which defeats my cunning ploy of making an elegant function for choosing constructors.

A possible solution is to change the keys in the hash to the class name, and use this when calling the constructor:

my %constructors = ( "One" => \&One::new,
                     "Two" => \&Two::new );

sub factorish {
    my ( $type, @arguments ) = @_;

    my $consref = $constructors{ $type }
        or die "No handler for $type.";

    return $consref -> ( $type, @arguments );
}

[download]

This is fine, but in cases where I don't know (nor care, for that matter) about the class name, this will not work. Am I trying something that is not possible, or is there a way around this?

pernod
--
Mischief. Mayhem. Soap.

In reply to Storing references to constructors with context by pernod

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