From: Simon Strandgaard <0bz63fz3m1qt3001@...>
Date: 2003-05-13T20:31:42+09:00
Subject: Re: State Pattern Implementation

On Tue, 13 May 2003 14:04:33 +0200, Robert Klemme wrote:

> 
> "Simon Strandgaard" <0bz63fz3m1qt3001@sneakemail.com> schrieb im
> Newsbeitrag news:pan.2003.05.13.11.04.00.160567@sneakemail.com...
>> On Tue, 13 May 2003 10:11:42 +0200, Robert Klemme wrote:
>>
>> > I'd like to hear what people think: is this a reasonable
> implementation of
>> > the state pattern?
>>
>> You are representing each state by a number... with the State pattern
>> isn't each state supposed to be represented by a class ?
> 
> Normally, yes.  The association with a number is just for the ease of
> keying the example in.  

OK.


> My main idea was to replace the state instance by
> a redefinition of instance methods.  

Interesting thought. So instead of having a state variable you redefine
some state-transition-methods. Clever :-)

Am I understanding you correct ?


> Pro is, you safe an instance and a redirection; 
> on the con side is increased code size for the class since
> you have to include code for all states.

Because you don't have an explicit state variable, the state becomes
implicit. Thus its hard to tell the current state..
Just a thought :-) 


> I'm curios to know whether anybody did this before.  I might be missing
> some grave disadvantage.

Kind of.. not tried the same. I have done some state machines from time to
time.

--
Simon Strandgaard