Scratch

markyparky56 wrote:

fullmoon wrote:

markyparky56 wrote:

But not the weirdest one, but the name I can not utter on the scratch forums.

Actually, I think the one you are referring to might have some competition: LOLCODE.

No, I mean this one I had to shorten the url. Warning, the name may be offensive to some people, I apologise, but you have been warned.

I know which one you meant, I just wanted to point out another one. Check out the Esoteric Programming Languages article on Wikipedia...

markyparky56 wrote:

But not the weirdest one

It would be weird to try to use that language for practical programming, but it's essentially the order code of the classic Turing machine, which Alan Turing invented to reason about computer programs.  For that purpose you want a language that's really simple, not a language that's really expressive, so your language isn't weird at all in that context.  Turing, for example, used that language to prove the Halting Theorem, which says that it's impossible to write a computer program that takes another computer program as input and determines, in finite time, whether that other program will halt (as opposed to infinitely looping) for a given input.  (You can detect loops in specific cases, but you can't write a loop detector that works for all possible programs.)

To bring this discussion slightly on topic: a contemporary of Turing, the mathematician Alonzo Church, invented at about the same time a language with a similar purpose--reasoning about programs--that turned out also to be very expressive (usable for practical programming): the lambda calculus!  (A/k/a THE BLOCK.)

bharvey wrote:

soupoftomato wrote:

I clicked that link and now it's saved to the main computers Mozilla history. How do I erase?

Tools>Clear Private History

or

Preferences>Advanced>Network>Clear Now
Preferences>Privacy>Clear Now

Thanks, but it was Tools>Clear Recent History

soupoftomato wrote:

Whenever I have tried to download updates, it gives me an Adobe Folder, that I can't open. 

That's strange.  Sounds like you have a bad association with some file extension.  What file can't it open, BYOB.image, or something else?

If BYOB.image, try right-clicking on it, choose "Open with" or "Send to" depending on OS, then choose BYOB.exe if you have it, or Scratch.exe in a pinch.  Or just drag BYOB.image onto one of those.

nXIII wrote:

bharvey wrote:

nXIII wrote:

I'll help! (You probably noticed my (very incomplete so far) thread)

Thanks!  I did notice it when you first started, when it was really incomplete, but I see you've made a lot of progress since then.  I'll read it seriously over the weekend.

No! Don't do that! I'm away over the weekend, (right now) so I can't work on it....

Now IS the weekend though... unless your already gone.

Jens wrote:

It's mostly GUI work, building morphic windows and dialog boxes etc.

nXIII wrote:

When I get back...

If you're really going to work on this (as opposed to linked lists    ), I think the issues are pedagogic as well as strictly GUI.  For example, the Smalltalk code behind a (primitive) block is in at least two different places: ScriptableScratchMorph>blockSpecs>blockSpecs and wherever the actual work is done (maybe three places if there is a Scratch-specific method that calls underlying Smalltalk stuff).  I think all of the relevant code should appear at once, in a single (paned) window, when you choose "edit Elements."

And somewhere there should be a "new primitive block" button that opens a BYOB-Make-a-block-like dialog in which you enter the block spec, not as text, but in pieces, actually almost identical to the Make-a-block dialog, so you choose a menu and you choose a shape etc.  And when you click OK on that dialog, that's when you get the Elements window, already positioned correctly for you to add the code that implements the method.  Maybe the initial dialog has two text fields, one for the surface appearance and one for the Smalltalk method name.  And instead of all-sprites vs this-sprite your choices are just-sprites, just-stage, or both.

And when you're browsing classes, you should get tooltips that explain from Scratch's point of view (i.e. not Smalltalk's) what this class is all about, to make it easier to find what you're looking for.  (Just recently I had occasion to look for where the Mac-specific file type and creator fields are set for projects and sprites, and I found it really hard.)

So you see, I think this is a little more work than Jens seems to think. 

PS Have a good vacation. 

markyparky56 wrote:

Wow... thats a very confusing comment

Basically what I'm saying is that a lot of the lore that you find in various people's how-to-mod tutorial threads ought to be visually apparent in Elements.

jstout wrote:

JSO wrote:

bharvey wrote:

Not a joke.  At various times in the past I've formed the intention of learning Smalltalk but always found the textbooks and/or the Squeak UI offputting.

Sad to say but it's the same for me 
Smalltalk is just so different from other programming languages...

I remember someone saying that Smalltalk needed about 6 months' work before you got the Aha! moment. I've come to the conclusion that you need a real project to really get up to speed since I've learnt more about using Smalltalk/Squeak in the last week or so since I've started adding to BYOB a Files category. I find Elements a little difficult to use since I'm a little prone to RSI when I use the mouse, so the normal Smalltalk/Squeak text based interface is much more productive for me.

After using it intensively I'd forgotten, in that old saying about ALGOL-60, just how much of an improvement Smalltalk was on most of its successors.

I'm doing a 2 minute nano-presentation to the UK's Computer At School's July conference in Birmingham at the end of next week on extending BYOB/Scratch, entirely in BYOB, using projects as live presentation slides, demonstrating the System Browser, showing a BYOB unless <predicate>, and then doing the same thing as a built in method. So I'll be using the system that I'm updating to do the presentation and the development, text editing, debugging (hopefully not needed), source code management, ... wish me luck! It's part of my push to use BYOB all the way up from using it with my 3 year old grandson to demonstrating functional programming with my 6th form (year 13 in the UK) students, then sideways into Smalltalk/Squeak to demonstrate OOP, then ...

There just isn't anything that I know of that gives me the same immediacy and single system approach (Oberon from Niklaus Wirth and Jürg Gutknecht at ETH is perhaps the closest: not surprisingly since I gather they were inspired to develop it by working at Xerox Parc).

John

Use hacked BYOB, downloadable on the Slash site.

jstout wrote:

I remember someone saying that Smalltalk needed about 6 months' work before you got the Aha! moment. I've come to the conclusion that you need a real project to really get up to speed since I've learnt more about using Smalltalk/Squeak in the last week or so since I've started adding to BYOB a Files category.

My problem is not the "aha moment"; I've heard Alan Kay and Dan Ingalls talk about the big ideas enough times (live at PARC, originally, and for the past 20-odd years on video, because I play them for my SICP students) to feel comfortable with those.

But there's a skill set I don't have, of finding where in the maze of code something actually happens.  The other day I was looking for the Share menu (I'm making the BYOB standalone-app feature work on the Mac as well as on Windows) but couldn't find it after a day of looking, until I happened to see another Scratch forum thread in which someone asked and nXIII answered how to change the Scratch logo to something else, and that steered me to Scratch-UI-Panes>ScratchFrameMorph>compiler.  But I didn't get there by searching for "menu" or "share" and would have had to fall back on asking Jens if I hadn't found that serendipitous hint from n.

I (almost) finished the Elements Inspector. I don't like the bottom pane, though, because it has to have a palette in it, which leaves too little room for coding. Should I just not include a palette and have the user drag in blocks from somewhere else?

EDIT: @Jens, I'm also having trouble with multiline UpdatingStringMorphs - they don't exist... do you mind if I add support for multiline strings?

Last edited by nXIII (2010-07-04 12:47:44)

bharvey wrote:

jstout wrote:

I remember someone saying that Smalltalk needed about 6 months' work before you got the Aha! moment. I've come to the conclusion that you need a real project to really get up to speed since I've learnt more about using Smalltalk/Squeak in the last week or so since I've started adding to BYOB a Files category.

My problem is not the "aha moment"; I've heard Alan Kay and Dan Ingalls talk about the big ideas enough times (live at PARC, originally, and for the past 20-odd years on video, because I play them for my SICP students) to feel comfortable with those.

But there's a skill set I don't have, of finding where in the maze of code something actually happens.  The other day I was looking for the Share menu (I'm making the BYOB standalone-app feature work on the Mac as well as on Windows) but couldn't find it after a day of looking, until I happened to see another Scratch forum thread in which someone asked and nXIII answered how to change the Scratch logo to something else, and that steered me to Scratch-UI-Panes>ScratchFrameMorph>compiler.  But I didn't get there by searching for "menu" or "share" and would have had to fall back on asking Jens if I hadn't found that serendipitous hint from n.

I was reduced a couple of times to searching through the source code for a string I knew that would be in there (not available in Elements but in the Squeak/Smalltalk), but after a pretty intensive week or so I reckon that I've got to know the main categories, and I find that isolates where I should be looking.

So, to take your example in Elements Scratch then Scratch-UI-Panes class category for anything to do with the user interface, ScratchFrameMorph for the 'overall' UI, menu/button actions method category and then shareMenu: which shows the selector #makeExe as the one associated with the compiler. Then in Squeak/Smalltalk I just did a Smalltalk browseAllImplementorsOf: #makeExe.

I find the extra facilities in Squeak/Smalltalk outweigh the drag and drop Elements system, not just because of my RSI. The specialist browsers help as well.

John

bharvey wrote:

jstout wrote:

Scratch then Scratch-UI-Panes class category for anything to do with the user interface,
John

How did you know it was Scratch-UI-Panes and not Scratch-UI-Dialogs, Scratch-UI-Watchers (okay, I guess that was unlikely), or Scratch-UI-Support?  I kept looking for a global search feature that would let me search for "compile" but at best I found the Smalltalk compiler rather than the (misnamed) BYOB app compiler.

It's a bit difficult to remember my thought process but I think I just looked at the classes in each of the categories and decided that Dialogs looked like dialogs, e.g., NewVariableDialog, Support looked a little too low-level, and Watchers, I assumed from the name and the classes, were to do with variables.

As I say, in Squeak/Smalltalk off the more... option on the main screen menu there's a

Were you using Elements or Squeak/Smalltalk?

I've kept a Workspace open with the hints to remind me of what I've learnt (another thing you don't get with Elements), here's what's in it:

"
ScratchViewerMorph is the category pane and blocks viewer
Methods:
    rebuildCategorySelectors
"
(ScratchFrameMorph allInstances at: 1)  startup "This is the one to do to recreate the category and block panes"

"
ScratchFrameMorph is the Scratch screen
Methods:
    createBasicFrames
    startup

ScratchSkin at: #pen gives you the form for the category (or in fact anything) (class variable for ScratchFrameViewer?)
"
ScratchSkin at: #files put: (ScratchSkin at: #pen)

"World is a PasteUpMorph"

ScratchFrameMorph writeAllSkins    "writes out all the current skins to GIF format in current directory"

ScratchFrameMorph readSkinFrom: (FileDirectory default directoryNamed: 'ScratchSkin')
"reads them back in"

ScratchFrameMorph updateSkinFrom: (FileDirectory default directoryNamed: 'ScratchSkin')

"ScriptableScratchMorph has block specs"

"Also has blockColorFor: Made HSV for file ops yellowish: h: 58 s: 0.80 v: 1.00"
"Added category file ops"

ScratchListMorph exportList/importList are useful

Some of things are just there because I tried them and they worked and they don't seem to cause any major problems.

I could browse, put self halt. anywhere that I thought was relevant to a problem and try it. If I brought up a debugger window then I could trace through the execution, find out where it had come from and so on. I could try stuff in Workspaces and I knew that if I ruined something then I just needn't save the image and I'd still have a working system.

John

jstout wrote:

I know this one is a bit contentious but could I make a plea for the cloning blocks to be linked in?

I think this is one of those "wait for 3.1" things.  We don't want to introduce new bugs at this point, and I'm sure there'd be some.     But we definitely want cloning.

Thanks for the Squeak hints.  (I'm using the Squeak browser, not Elements.)