/ 
KinoSearch-0.30_07
River stage two • 9 direct dependents • 10 total dependents
/ KinoSearch::Obj

NAME

KinoSearch::Obj - Base class for all KinoSearch objects.

SYNOPSIS

package MyObj;
use base qw( KinoSearch::Obj );

# Inside-out member var.
my %foo;

sub new {
    my ( $class, %args ) = @_;
    my $foo = delete $args{foo};
    my $self = $class->SUPER::new(%args);
    $foo{$$self} = $foo;
    return $self;
}

sub get_foo {
    my $self = shift;
    return $foo{$$self};
}

sub DESTROY {
    my $self = shift;
    delete $foo{$$self};
    $self->SUPER::DESTROY;
}

DESCRIPTION

All objects in the KinoSearch:: hierarchy descend from KinoSearch::Obj. All classes are implemented as blessed scalar references, with the scalar storing a pointer to a C struct.

Subclassing

The recommended way to subclass KinoSearch::Obj and its descendants is to use the inside-out design pattern. (See Class::InsideOut for an introduction to inside-out techniques.)

Since the blessed scalar stores a C pointer value which is unique per-object, $$self can be used as an inside-out ID.

# Accessor for 'foo' member variable.
sub get_foo {
    my $self = shift;
    return $foo{$$self};
}

Caveats:

  • Inside-out aficionados will have noted that the "cached scalar id" stratagem recommended above isn't compatible with ithreads -- but KinoSearch doesn't support ithreads anyway, so it doesn't matter.

CONSTRUCTOR

new()

Abstract constructor -- must be invoked via a subclass. Attempting to instantiate objects of class "KinoSearch::Obj" directly causes an error.

Takes no arguments; if any are supplied, an error will be reported.

DESTRUCTOR

DESTROY

All KinoSearch classes implement a DESTROY method; if you override it in a subclass, you must call $self->SUPER::DESTROY to avoid leaking memory.

METHODS

to_string()

Generic stringification: "ClassName@hex_mem_address".

equals(other)

Indicate whether two objects are the same. By default, compares the memory address.

  • other - Another Obj.

dump()

Return a representation of the object using only scalars, hashes, and arrays. Some implementations support JSON serialization via dump() and its companion method, load(); for others, dump() is only a debugging aid. The default simply calls to_string().

ABSTRACT METHODS

to_i64()

Convert the object to a 64-bit integer.

to_f64()

Convert the object to a double precision floating point number.

load(dump)

Create an object from the output of a call to dump(). Implementations should not reference the caller.

  • dump - The output of dump().

COPYRIGHT AND LICENSE

Copyright 2005-2009 Marvin Humphrey

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.