package MyClassUsingArraysAsInternalStorage;
use Class::XSAccessor::Array
constructor => 'new',
getters => {
get_foo => 0, # 0 is the array index to access
get_bar => 1,
},
setters => {
set_foo => 0,
set_bar => 1,
},
accessors => { # a mutator
buz => 2,
},
predicates => { # test for definedness
has_buz => 2,
},
lvalue_accessors => { # see below
baz => 3,
},
true => [ 'is_token', 'is_whitespace' ],
false => [ 'significant' ];
# The imported methods are implemented in fast XS.
# normal class code here.
As of version 1.05, some alternative syntax forms are available:
package MyClass;
# Options can be passed as a HASH reference if you prefer it,
# which can also help PerlTidy to flow the statement correctly.
use Class::XSAccessor {
getters => {
get_foo => 0,
get_bar => 1,
},
};
A simple benchmark showed a significant performance advantage over writing accessors in Perl.
Since version 0.10, the module can also generate simple constructors (implemented in XS) for you. Simply supply the "constructor => 'constructor_name'" option or the "constructors => ['new', 'create', 'spawn']" option. These constructors do the equivalent of the following Perl code:
sub new {
my $class = shift;
return bless [], ref($class)||$class;
}
That means they can be called on objects and classes but will not clone objects entirely. Note that any parameters to new() will be discarded! If there is a better idiom for array-based objects, let me know.
While generally more obscure than hash-based objects, objects using blessed arrays as internal representation are a bit faster as its somewhat faster to access arrays than hashes. Accordingly, this module is slightly faster (~10-15%) than Class::XSAccessor, which works on hash-based objects.
The method names may be fully qualified. In the example of the synopsis, you could have written "MyClass::get_foo" instead of "get_foo". This way, you can install methods in classes other than the current class. See also: The "class" option below.
Since version 1.01, you can generate extremely simple methods which just return true or false (and always do so). If that seems like a really superfluous thing to you, then think of a large class hierarchy with interfaces such as PPI. This is implemented as the "true" and "false" options, see synopsis.
use Class::XSAccessor::Array
getters => {
get_foo => 0,
},
replace => 1;
The list of available options is:
As with the other options, "chained" affects all methods generated in the same "use Class::XSAccessor::Array ..." statement.
The following example demonstrates an lvalue accessor:
package Address;
use Class::XSAccessor
constructor => 'new',
lvalue_accessors => { zip_code => 0 };
package main;
my $address = Address->new(2);
print $address->zip_code, "\n"; # prints 2
$address->zip_code = 76135; # <--- This is it!
print $address->zip_code, "\n"; # prints 76135
Scary code exploiting strange XS features.
If you think writing an accessor in XS should be a laughably simple exercise, then please contemplate how you could instantiate a new XS accessor for a new hash key or array index that's only known at run-time. Note that compiling C code at run-time a la Inline::C is a no go.
Threading. With version 1.00, a memory leak has been fixed that would leak a small amount of memory if you loaded "Class::XSAccessor"-based classes in a subthread that hadn't been loaded in the ``main'' thread before. If the subthread then terminated, a hash key and an int per associated method used to be lost. Note that this mattered only if classes were only loaded in a sort of throw-away thread.
In the new implementation as of 1.00, the memory will not be released again either in the above situation. But it will be recycled when the same class or a similar class is loaded again in any thread.
chocolateboy <chocolate@cpan.org>
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8 or, at your option, any later version of Perl 5 you may have available.