As it happens, merlyn posted something similar the other day, which you could adapt easily (untested)...

# in Astro::Observation

sub new {
    my $self  = shift;

    # Foo->new('bar',@_) => Foo::Bar->new(@_)

    my $class = __PACKAGE__ . "::" . ucfirst(shift);

    require autouse;
    autouse->import( $class, "$class\::new" );

    return $class->new( @_ );
}
[download]

Update:

... or not.

After trying out the above, I kept getting the error "autouse into different package attempted", which appears to be a known bug in autouse when using a module that isn't at the root of it's namespace (ie, Foo would work, but Foo::Bar doesn't).

Perhaps merlyn has a patched version of autouse?

Anyhoo, another way to do it (and as jeffa suggests) is with eval...

sub new {
    my $self  = shift;

    # Foo->new('bar',@_) => Foo::Bar->new(@_)

    my $class = __PACKAGE__ . "::" . ucfirst(shift);

    eval "require $class;"; # Note: "" *NOT* {} !

    if ( $@ ) {      # whoops, there was an error
        warn( $@ );  # require'ing $class; perhaps
        return;      # it doesn't exist?
    }

    return $class->new( @_ );
}
[download]

    --k.

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.