Hi alan

Simply because I could not master it. I'm too programming-language 
oriented and I wanted to tell another story. eToy is event based and 
concurrent and I wanted to be sequential. All in all in the end is good 
because we will have multiple
material for teachers. I still think that a good book on using eToy 
would be great and hope kim will have one soon. I hope to finish the 
first book before the summer.

Stef



On Saturday, April 5, 2003, at 03:21 PM, Alan Kay wrote:

> Why not just do this in the Etoys authoring environment?
>
> Cheers,
>
> Alan
>
> -------
>
> At 2:16 PM +0200 4/5/03, Stephane Ducasse wrote:
>> Hi bob
>>
>> I want to implement a robot a la Karel that novices can program.
>> Using the step mechanism for that is not clear for me because the 
>> idea is that kids
>> can define any kind of method in terms of the simple elementary one. 
>> So I have everything working except this problem with the refresh of 
>> the world.
>>
>> I have to  think about your solution with the calculatePositionAt:
>>
>> On Saturday, April 5, 2003, at 01:45 PM, Bob Arning wrote:
>>
>>> On Sat, 5 Apr 2003 10:37:01 +0200 Stephane Ducasse 
>>> <ducasse at iam.unibe.ch> wrote:
>>>> I have the impression that this is a really bad practice to 
>>>> explicitly
>>>> wait for the refresh but I do not know how to do it in a better way.
>>>>
>>>> Have you suggestion to fix my problem?
>>>
>>> It sounds as if you really want to slow the robot down to some sort 
>>> of "realistic" rate of progress so that you can actually see it 
>>> doing stuff. The morphic approach would be to use a #step method...
>>>
>>> step
>>>
>>> 	position _ self calculatePositionAt: Time millisecondClockValue.
>>> 	self goTo: position.
>>> 	self canPick ifTrue: [self pick].
>>>
>>> and make this run as often as possible...
>>>
>>> stepTime
>>>
>>> 	^1
>>>
>>> Cheers,
>>> Bob
>>>
>>>
>> Prof. Dr. Stéphane DUCASSE
>> http://www.iam.unibe.ch/~ducasse/
>>  "if you knew today was your last day on earth, what would you do 
>> different? ...  especially if,
>>  by doing something different, today might not be your last day on 
>> earth" Calvin&Hobbes
>>
>> "The best way to predict the future is to invent it..." Alan Kay.
>>
>> Open Source Smalltalks: http://www.squeak.org, 
>> http://www.gnu.org/software/smalltalk/smalltalk.html
>> Free books for Universities at 
>> http://www.esug.org/sponsoring/promotionProgram.html
>> Free Online Book at 
>> http://www.iam.unibe.ch/~ducasse/WebPages/FreeBooks.html
>
>
> -- 
>
>
>
Prof. Dr. Stéphane DUCASSE
http://www.iam.unibe.ch/~ducasse/
  "if you knew today was your last day on earth, what would you do 
different? ...  especially if,
  by doing something different, today might not be your last day on 
earth" Calvin&Hobbes

"The best way to predict the future is to invent it..." Alan Kay.

Open Source Smalltalks: http://www.squeak.org, 
http://www.gnu.org/software/smalltalk/smalltalk.html
Free books for Universities at 
http://www.esug.org/sponsoring/promotionProgram.html
Free Online Book at 
http://www.iam.unibe.ch/~ducasse/WebPages/FreeBooks.html