NAME¶
Object::Tiny - Class building as simple as it gets
SYNOPSIS¶
# Define a class
package Foo;
use Object::Tiny qw{ bar baz };
1;
# Use the class
my $object = Foo->new( bar => 1 );
print "bar is " . $object->bar . "\n";
DESCRIPTION¶
There's a whole bunch of class builders out there. In fact, creating a class
builder seems to be something of a rite of passage (this is my fifth, at
least).
Unfortunately, most of the time I want a class builder I'm in a hurry and
sketching out lots of fairly simple data classes with fairly simple structure,
mostly just read-only accessors, and that's about it.
Often this is for code that won't end up on CPAN, so adding a small dependency
doesn't matter much. I just want to be able to define these classes FAST.
By which I mean LESS typing than writing them by hand, not more. And I don't
need all those weird complex features that bloat out the code and take over
the whole way I build modules.
And so, I present yet another member of the Tiny family of modules,
Object::Tiny.
The goal here is really just to save me some typing. There's others that could
do the job just fine, but I want something that does as little as possible and
creates code the same way I'd have written it by hand anyway.
To use Object::Tiny, just call it with a list of accessors to be created.
use Object::Tiny 'foo', 'bar';
For a large list, I lay it out like this...
use Object::Tiny qw{
item_font_face
item_font_color
item_font_size
item_text_content
item_display_time
seperator_font_face
seperator_font_color
seperator_font_size
seperator_text_content
};
This will create a bunch of simple accessors, and set the inheritance to be the
child of Object::Tiny.
Object::Tiny is empty other than a basic "new" constructor which does
the following
sub new {
my $class = shift;
return bless { @_ }, $class;
}
In fact, if doing the following in your class gets annoying...
sub new {
my $class = shift;
my $self = $class->SUPER::new( @_ );
# Extra checking and such
...
return $self;
}
... then feel free to ditch the SUPER call and just create the hash yourself!
It's not going to make a lick of different and there's nothing magic going on
under the covers you might break.
And that's really all there is to it. Let a million simple data classes bloom.
Features? We don't need no stinking features.
Handling Subclasses¶
If the class you are using Object::Tiny for is already a subclass of another
Object::Tiny class (or a subclass of anything else) it doesn't really work to
make the class use multiple inheritance.
So in this case, Object::Tiny will create the accessors you specify, but WON'T
make it a subclass of Object::Tiny.
Why bother when Class::Accessor::* already does the same thing?¶
As a class builder, Object::Tiny inevitably is compared to Class::Accessor and
related modules. They seem so similar, so why would I reimplement it?
The answer is that for experienced developers that don't need or want
hand-holding, Object::Tiny is just outright better, faster or cheaper on every
single metric than Class::Accessor::Fast, which is the most comparable member
of the Class::Accessor::* family.
Object::Tiny is 93% smaller than Class::Accessor::Fast
Class::Accessor::Fast requires about 125k of memory to load.
Object::Tiny requires about 8k of memory to load.
Object::Tiny is 75% more terse to use than Class::Accessor::Fast
Object::Tiny is used with the least possible number of keystrokes (short of
making the actual name Object::Tiny smaller).
And it requires no ugly constructor methods.
I mean really, what sort of a method name is 'mk_ro_accessors'. That sort of
thing went out of style in the early nineties.
Using Class::Accessor::Fast...
package Foo::Bar;
use base 'Class::Accessor::Fast';
Foo::Bar->mk_ro_accessors(qw{ foo bar baz });
Using Object::Tiny...
package Foo::Bar;
use Object::Tiny qw{ foo bar baz };
Further, Object::Tiny lets you pass your params in directly, without having to
wrap them in an additional HASH reference that will just be copied ANYWAY
inside the constructor.
Using Class::Accessor::Fast...
my $object = Foo::Bar->new( {
foo => 1,
bar => 2,
baz => 3,
} );
Using Object::Tiny...
my $object = Foo::Bar->new(
foo => 1,
bar => 2,
baz => 3,
);
Object::Tiny constructors are 110% faster than Class::Accessor::Fast
Object::Tiny accessors are identical in speed to Class::Accessor::Fast
accessors, but Object::Tiny constructors are TWICE as fast as
Class::Accessor::Fast constructors, DESPITE C:A:Fast forcing you to pass by
reference (which is typically done for speed reasons).
Benchmarking constructor plus accessors...
Rate accessor tiny
accessor 100949/s -- -45%
tiny 182382/s 81% --
Benchmarking constructor alone...
Rate accessor tiny
accessor 156470/s -- -54%
tiny 342231/s 119% --
Benchmarking accessors alone...
Rate tiny accessor
tiny 81.0/s -- -0%
accessor 81.0/s 0% --
Object::Tiny pollutes your API 95% less than Class::Accessor::Fast
Object::Tiny adds two methods to your class, "new" and
"import". The "new" constructor is so trivial you can just
ignore it and use your own if you wish, and the "import" will
shortcut and do nothing (it is used to implement the "use Object::Tiny
qw{ foo bar baz };" syntax itself).
So if you make your own import, you can ignore the Object::Tiny one.
Class::Accessor::Fast isn't quite as light, adding all sorts of useless extra
public methods (why on earth would you want to add method accessors at
run-time?).
Here's what the classes used in the benchmark end up like.
DB<1> use Class::Inspector
DB<2> x Class::Inspector->methods('Foo_Bar_Tiny');
0 ARRAY(0xfda780)
0 'bar'
1 'baz'
2 'foo'
3 'import'
4 'new'
DB<3> x Class::Inspector->methods('Foo_Bar_Accessor');
0 ARRAY(0xfdb3c8)
0 '_bar_accessor'
1 '_baz_accessor'
2 '_carp'
3 '_croak'
4 '_foo_accessor'
5 '_mk_accessors'
6 'accessor_name_for'
7 'bar'
8 'baz'
9 'best_practice_accessor_name_for'
10 'best_practice_mutator_name_for'
11 'follow_best_practice'
12 'foo'
13 'get'
14 'make_accessor'
15 'make_ro_accessor'
16 'make_wo_accessor'
17 'mk_accessors'
18 'mk_ro_accessors'
19 'mk_wo_accessors'
20 'mutator_name_for'
21 'new'
22 'set'
As you can see, Object::Tiny adds 2 methods to your class, Class::Accessor adds
16 methods, plus one extra one for every accessor.
Object::Tiny doesn't have any of the caveats of Class::Accessor::Fast
When you call
use Object::Tiny qw{ foo bar baz } it isn't treated as some
sort of specification for the class, it's just a list of accessors you want
made for you.
So if you want to customize "foo" you don't need to get into
contortions with "pure" base classes or calling alternate internal
methods. Just make your own "foo" method and remove "foo"
from the list passed to the "use" call.
Object::Tiny is more back-compatible than Class::Accessor::Fast
Class::Accessor::Fast has a minimum Perl dependency of 5.005002.
Object::Tiny has a minimum Perl dependency of 5.004.
Object::Tiny has no module dependencies whatsoever
Object::Tiny does not load ANYTHING at all outside of its own single .pm file.
So Object::Tiny will never get confused in odd situations due to old or weird
versions of other modules (Class::Accessor::Fast has a dependency on base.pm,
which has some caveats of its own).
SUPPORT¶
Bugs should be reported via the CPAN bug tracker at
<
http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Object-Tiny>
For other issues, contact the author.
AUTHOR¶
Adam Kennedy <adamk@cpan.org>
SEE ALSO¶
Config::Tiny
COPYRIGHT¶
Copyright 2007 - 2008 Adam Kennedy.
This program is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.
The full text of the license can be found in the LICENSE file included with this
module.