Scratch

You could try copy/pasting these. 

Appreciating the Google logo today Brian? 

Suggestion: a <(list) is linked?> block, so you could make higher order functions fast for both representations of lists!
For example, the map block could be

if <(list) is linked?>
report <<call (func) with inputs (item (1 v) of (list))> in front of <map (func) over <all but first of (list)>>>
else
script variables (result) (index)
set [index v] to (1)
set [result v] to (list) //supposed to be the empty list, not the list variable (they are indistinguishable by the scratchblocks tag)
repeat (length of (list)) //supposed to be the red length of block
add (item (index) of (list)) to (result)
change [index v] by (1)
end
report (result)
end

Last edited by joefarebrother (2012-06-23 03:46:55)

joefarebrother wrote:

Suggestion: a <(list) is linked?> block

I'm of two minds about this.  What makes it not a no-brainer is that if possible I'd rather not surface that distinction at all; I have a Scratch-Team-like fear that it'd confuse people who don't know anything about data structures.

If someone is using MAP then they're doing functional programming and that list should be converted to linked form if necessary.  FOR EACH is the example you should be citing.  A purist would say that that's not functional and so the list should be converted to array form.

Maybe we compromise on some kludge, e.g., if you shift-click the pulldown in the IS A block, it offers you more choices, e.g., INTEGER, NON-INTEGER NUMBER, LINKED LIST, DYNAMIC ARRAY, etc.  Jens would hate that, though, I'm guessing.

Jens wrote:

How did you guess? 

Well, there you are, then.  I'm not too worried about this sort of timing problem, anyway, because converting between formats takes linear time, and so an extra conversion thrown into a MAP or FOR EACH will only slow things down by at most a constant factor (since MAP and FOR EACH take linear time, too).

blob8108 wrote:

Hardmath123 wrote:

now I'm inspired to make a Scratch-like environment for this tape stuff. 

I believe it's called a Turing Machine, if you're interested. 

I only just noticed that Hardmath said "Scratch-like environment" instead of "Turing machine in Scratch."  You do realize, right, Hardmath, that the official representation of a Turing machine (apart from the tape) is already graphical?  It's a state diagram, like a finite state machine but with tape actions associated with the transitions.

Hardmath123 wrote:

I'm sure Scratch is powerful enough to handle making something like that.

Yes, because the Turing machine uses the (theoretically infinite) tape to record the intermediate states of the computation, instead of recursion.  So all you have to write is the finite state machine that handles each state change on the tape.

Taneb wrote:

It definitely is sufficiently powerful: I've written an interpreter for the Turing-Complete language [removed] in Scratch.
[mod note - please do not refer to inappropriate names]

I just don't understand that language lol.

Last edited by scimonster (2012-06-26 08:37:39)

A couple of BYOB demos now converted to run in Snap!:

tree.xml

animal-game.xml

Hardmath123 wrote:

I have a feeling I've officially picked up too many coding projects. 

Haha, i know the feeling.

I'm ashamed to be asking this question, but how do you import xml files?

shadow_7283 wrote:

I'm ashamed to be asking this question, but how do you import xml files?

Don't be ashamed.  It's our fault for not having a robust save/load up yet.

MathWizz wrote:

EDIT: And don't forget to delete it from the desktop. You don't want it to clutter the place up, do you? 

It doesn't have to be the desktop; you can drag from any open folder!  I made a SnapProjects folder on my desktop.