Scratch

Is there a way to make a boolean and/or number only input in BYOB blocks?

I created a new block and used a "when I receive" block inside it by adding a new message for it. When I saved the block I couldn't find the newly defined message in the message names available in the "broadcast" block.

Is this a bug or a wanted behaviour?

please click em!

Hi Stefano,

In current BYOB you can only attach blocks to the template (the function header), everyting else will not be saved in the function definition. This includes "when I receive" event hat blocks (although I agree those would make a formidable additon to function definitions, allowing for almose lambda-wise constructs...).

About those associative arrays, I guess these would correspond to Dictionaries in Smalltalk or Python and would not be hard to implement for Scratch at all. In fact, my very first List prototype (which ist still available for download) was designed on top of Dictionaries (but only used those to fake a Sequential Collection which would not have to be dimensioned or accessed sequentially. So, I'm curious in which other ways  Scratch could benefit from associative Arrays

Jens wrote:

So, I'm curious in which other ways  Scratch could benefit from associative Arrays

Some examples in my kids' Scratch work ...

- a Grapher to store a list of (x,y) points: Dictionary[x->y] works well
- track [Person -> Hi Score] for a game

btw, Jens, is the current BYOB source available? Is there any info on how to get started browsing the BYOB image in Squeak and playing around with it?

Last, any idea who I might ping to see about getting the email notifications option working on this forum?

Thanks! -- Sophie

I'm trying to fill a triangle in BYOB like dapontes did in this project:

http://scratch.mit.edu/projects/dapontes/230203

Unfortunately BYOB is not able to do the block

<move( (( v <*> (( AC </> AB )) )) )steps>

from the sprite "help2". I always get an internal error.

When I try the code in Scratch 1.4, I don't get any errors. Can somebody help?

Hi Jens,

I just sent you an e-mail.

Thanks in advance
Thilo

Hi, The-Whiz,

I'm afraid I don't fully understand your question.
You can put any reporter block into the argument placeholders of your custom blocks in BYOB. Yes, that includes booleans, numbers and text. Can you specifically confine a custom block's parameter to a certain type? No. Can you create a custom block which lets users input boolean values via the keyboard? I guess that's up to your creativity 

Jens - Any thoughts on feasibility of parameters and variables accepting lists and sprites, in addition to numbers, strings, and booleans?

minor bug fixes

I just fixed a couple of minor bugs relating to the BYOB error detection mechanism (the red outline around erroneous blocks, e.g. divisions by zero) and pushed the release number to BYOB 2.0.1. Be sure to empty your browser's cache before you download the zip file again, and to check if your downloaded version show this number. Thank you, Thilo, for notifying me about the bug in mention!

Hey... iv download BYOB and iv tried it out.

Three things.

1. I cant open any of the examples, they might be corrupted or something.

2. Iv tried the make block. All i can make is math type blocks, with varibles. (Am i doing something wrong here?)

3. Someone said that the mesh was in BYOB. Is that true? or is just you make make it?

Jens wrote:

Another idea would be to introduce a kind of generic object-pointer reporter...

I'm inclined towards this generic reporter. I have not thought much through the implications, but I don't think it would be any more error prone than the alternatives, and would be simpler to understand.

Would the reporter probably take a string parameter & return the object reference?

Would it be feasible for this facility to include (something that encapsulated) squeak blocks or message symbols with some #perform: or #value like behavior predefined? So I can do

sprite perform: (self objectPointerReporter: 'method') with: (self objectPointerReporter: 'listA') ?

Regards --- Sophie

[Btw, behind all this I have a feeling that being able to do targeted invocations would be a big step, if it can be done consistent with Scratch's concurrency. Even to use your new (and fantastic!) composite sprites, the parent frequently needs to interact with its children, and I cannot see out how to do this cleanly with just global events].