Re: Usage of +class
Re: Usage of +class
- Subject: Re: Usage of +class
- From: j o a r <email@hidden>
- Date: Sat, 22 Apr 2006 18:00:38 +0200
On 22 apr 2006, at 17.42, Jonathon Mah wrote:
A class identifier has two uses: a _type_, and a message receiver.
Contrast this to a variable, which has two uses: a _value_, and a
message receiver.
I think you say "variable" where you mean "object" (instance of a
class). A variable has a type, and can hold a value. If that value is
an object (class or instance), you can send messages to it. Consider
the following entities:
Class Name
Class Object
Object (Instance of Class)
When you send class messages to the class name, you're really sending
them to the class object. Using the class name is just a shorthand /
convenience. This convenience (substitution of the class object for
the class name) doesn't work elsewhere, for example when passing
class objects as parameters to methods.
Interestingly, you can change the use of a class name from a type
to a value:
I think you're just playing with the _scope_ of variables here.
j o a r
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