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{include resources/header.md}
<div class="contents">
<div class="system-links">
* [Mailing Lists][3]
* [Getting it][4]
{remark * [Documentation][5]}
* [News][6]
{remark * [Test results][tr]}
* [Changelog][7]
[3]: #mailing-lists
[4]: #downloads
[5]: documentation/ "documentation link"
[6]: #news
[7]: changelog.html
[tr]: test-report.html
</div>
<div class="system-description">
### What it is
Class-mixins are a great idea but sometimes they lead to a
proliferation of subclasses with names like
`printable-touchable-composing-colored-shape-square-mixin`
and that's just ugly. Common-Lisp is a dynamic-programming
language; Dynamic-Classes brings dynamism to class
definition!
You define the mixins and associate them with parameters.
Then you
As an example, here is some code from [cl-containers][]
iterators that hooks parameters to iterator mixins:
(add-parameter->dynamic-class
:iterator :transform 'transforming-iterator-mixin)
(add-parameter->dynamic-class
:iterator :filter 'filtered-iterator-mixin)
(add-parameter->dynamic-class
:iterator :unique 'unique-value-iterator-mixin)
(add-parameter->dynamic-class
:iterator :circular 'circular-iterator-mixin)
and here it is in action:
> (let ((i (make-iterator '(1 2 3))))
(loop repeat 5 when (move-forward-p i) do
(print (next-element i))))
1
2
3
nil
> (let ((i (make-iterator '(1 2 3) :circular t)))
(loop repeat 5 when (move-forward-p i) do
(print (next-element i))))
1
2
3
1
2
> (let ((i (make-iterator '(1 2 3) :circular t :transform #'sqrt)))
(loop repeat 5 when (move-forward-p i) do
(print (next-element i))))
1.0
1.4142135
1.7320508
1.0
1.4142135
The `make-iterator` function calls `determine-iterator-class`
to handle the work of figuring how (and possibly creating)
the right class given the parameters.
(defmethod make-iterator
(iteratee &rest args &key (iterator-class nil) &allow-other-keys)
(apply #'make-instance
(apply #'determine-iterator-class iteratee iterator-class args)
:container iteratee
args))
Dynamic-Classes can make prototyping a breeze (and it's lots
of fun too)!
{anchor mailing-lists}
### Mailing Lists
* [dynamic-classes-devel][devel-list]: A list for announcements, questions, patches, bug reports, and so on; It's for everything _but_ the sinking kitchen.
{anchor downloads}
### Where is it
metabang.com is switching from [darcs][] to [git][]
for source control; the current dynamic-classes repository is on
[github][github-dynamic-classes] and you can clone it using:
git clone git://github.com/gwkkwg/dynamic-classes
Dynamic-Classes is also [ASDF installable][]. Its CLiki home
is right [where][cliki-home] you'd expect.
There's also a handy [gzipped tar file][tarball].
{anchor news}
### What is happening
2010 Dec 21
moved to github.
2008-May-26
We've split off from metatilities and are living large and on
our own! More tests and documentation coming ... soon (we
hope).
</div>
</div>
{include resources/footer.md}
|
