On 2012-07-13, "Eugene Leonovich" <gen.w...@gmail.com> wrote: > I'm a bit confused by the "class" keyword in the syntax ClassName::class. > We already have the magic constant __CLASS__ which does exactly the same > class name resolving, if you refer it within the class. > > So why to introduce a new keyword instead of using __CLASS__, like > ClassName::__CLASS__?
"class" is already a keyword, making it a simpler, easier to remember, and easier to type choice. > "Ralph Schindler" <ra...@ralphschindler.com> wrote in message > news:4f89d4f1.8070...@ralphschindler.com... >> Hi all, >> >> There are many different use cases were in code we expect classes names as >> arguments to functions as fully qualified names. We do this in ZF a lot >> with our Service Location and DI components, but also with our code >> reflection API, etc. A more interesting use case I would like to call out >> is with PHPUnit, for example in a test, you might find this: >> >> $mock = $this->getMock('A\Namespaced\ClassName'); >> >> This becomes cumbersome when you are dealing with lots of strings about >> lots of class names. This is also an area where, currently, namespace >> declaration and use statements offer no real support. >> >> The patch located here: >> >> https://github.com/ralphschindler/php-src/commit/02210d51851a96d723fbedcfc64cde9f9ae2b22a >> >> ... implements the ability for a developer to leverage the file's >> namespace declaration and use statements to be able to produce a scalar >> (string) of the class name that can be then used, for example, as an >> argument to a function elsewhere. >> >> This overloads the "class" keyword, and by virtue of the existing usage of >> "class" this feature is completely backwards compatible. All existing >> tests pass. For example, the above PHPUnit snipped would become: >> >> use A\Namespaced\ClassName; >> $mock = $this->getMock(ClassName::class); >> >> Another example with reflection: >> >> use SomeOther\FullyNamespaced\ClassElsewhere as CE; >> $r = new ReflectionClass(CE::class); >> >> More examples from the test file: >> >> namespace Foo\Bar { >> class Baz {} >> var_dump(Moo::CLASS); // "Foo\Bar\Moo" >> } >> >> namespace { >> use Bee\Bop as Moo, >> Foo\Bar\Baz; >> >> var_dump(Baz::class); // "Foo\Bar\Baz" >> var_dump(Boo::class); // "Boo" >> var_dump(Moo::CLASS); // "Bee\Bop" >> var_dump(\Moo::Class); // "Moo" >> >> $class = Baz::class; // assign class as scalar to var >> $x = new $class; >> var_dump($x); object(Foo\Bar\Baz)#1 (0) {} >> } >> >> >> What do you guys think? >> >> -ralph > > -- Matthew Weier O'Phinney Project Lead | matt...@zend.com Zend Framework | http://framework.zend.com/ PGP key: http://framework.zend.com/zf-matthew-pgp-key.asc -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
