General store

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1

I’m looking for a general method to store Snap! data in text format, as a layer upon the Database library. Functions in the Database library accept text and numbers only (and probably numbers are considered text as well).

A “general” method will support all of Snap!’s native data types (IMO a logical consequence of all data being 1st class). By “support” I mean:

  1. any data can be converted to a storable (text) format;
  2. recalled data can be restored without loss of information / accuracy.

Let’s have a look at each data type, and how it can be stored & restored:

  • number, text: trivial;
  • Boolean: would have to be characterized as a separate type;
  • list: JSON-conversion available in Snap! , both ways (but only for list containing numbers, text, Booleans, and sub-lists);
  • sprite (edit): (position, direction, rotation mode, shown?, size, color (?), graphic effects, … ?)
  • costume: fully defined (?) by: name, pixels (RGBA), width, height; available in Snap!.
  • sound: may be defined using a list of samples (?), sample frequency, and duration; but how can that be reported from an existing sound?
  • command, reporter, predicate: @joecooldoo made a converter to text, but the reverse conversion needs help from a library containing the very functions that are recalled; so I’m not sure how this will work.

Suggestions, anyone?

2

You can get the data, just like a costume, but with the of sound block
untitled script pic (26)

3

I can see that.

But how can the data this function reports be translated to inputs of
Programming tools DEVLAB script pic 20 ?

4

The list input is the samples, and the number input is the sample rate.

5

actually, vector costumes cannot be manipulated in Snap!, so they cannot be converted without loss of data.
(I don't think anyway)

6

somes examples in this project

Don't work for sprites and blocks

it's a start !

7

Snap!, of course, already has this capability internally; that's how we save and load projects. One tricky part is making sure to follow dependency chains, i.e., if you serialize a procedure, you have to also serialize any other procedures that the one you want calls.

So my point is, you shouldn't have to invent text formats for things; you can just use the formats that we already use.

8

1st-class-everything

first class projects when? /hj

9

I take the "h" in "hj" to mean that you actually do want an answer to that question, so here it is: Projects can't be first class in a project, because by definition there's only one project in a project. (Scenes are a fairly recent exception, and it would be theoretically possible to consider first class scenes, so a project could create a new scene in itself, but I don't think that actually makes sense either, because you can't edit a scene from within the project; you have to make the scene as its own project and then include it within the larger project.)

If the cloud provided a filesystem, like Google Drive etc., then the filesystem would have projects in it, and it'd be meaningful to ask what first class projects would mean in that context.