sokoban.love/representation.md

1.7 KiB

The on-disk representation of freewheeling apps

When you start up a freewheeling app, you'll see a directory printed out in the parent terminal (always launch it from a terminal window):

new edits will go to /home/...

When editing such an app using the driver (see README.md), new definitions will go into this directory. Let's call it $SAVE_DIR in the rest of this doc.

It is always safe to move such definitions into this repo. (We'll call it . in the rest of this doc.) You'll want to do this if you're sharing them with others, and it's also helpful if the driver crashes on your app. Moving definitions will never, ever change app behavior.

$ mv -i $SAVE_DIR/[0-9]* .  # should never clobber any existing files
$ mv $SAVE_DIR/head .  # expected to clobber the existing file

Try looking inside the head file with a text editor. It'll contain a number, the current version of the manifest for this app. For example:

478

This means the current state of the app is in a file called 0478-fwmanifest. If you moved the files you should see such a file in .. If you open this file, you'll see a JSON table from definition names to version ids. For example:

{ "a": 273, "b": 478}

This means the current definition of a is in 0273-a and of b in 0478-b.

Poking around these files gets repetitive, so there's a tool to streamline things:

lua tools/stitch-live.lua 0478-fwmanifest

stitch-live.lua takes a manifest file as its argument, and prints out all the definitions that make up the app at that version.

To compare two versions of the app, use stitch-live.lua to copy the definitions in each into a separate file, and use a file comparison tool (e.g. diff) to compare the two files.