[WIP] Implementation Plan

[sahandevs]

Machine Definition

Defining https://www.w3.org/2011/04/SCXML/scxml.xsd with dart models.

Translation

Convert a machine that user provides to the machine definition format.

• machine.fromJson : xstatejs format
• machine.fromSCXML: scxml format

Interpreter

An interpreter takes one Machine Definition (required), one Initial State and zero or more hooks and returns a Machine Instance.

Hooks

hook to an internal event of the interpreter. (onRaiseError, onStateChanged, ... )

Machine Instance

provides these properties:

• Stream<State> state: current state of the machine
  • State :
    • value: current state value
    • matches(State pattern): check if the state matches a pattern
    • context
• void send(Event event): sends event to the machine

Flutter

• Basic binding for flutter
• Provide a simple example

Basic Tooling

• Machine definition validation & auto completion
  • provide schema validation for Machine.fromJson with https://github.com/davidkpiano/xstate/pull/960/files#diff-573778b9503823ca0d77478e05c11054
  • provide validation for Machine.fromSCXML with https://www.w3.org/2011/04/SCXML/scxml.xsd
  • provide auto completion for target transition states
  • provide error for invalid or impossible transitions
• state.matches() validation & auto completion
  • provides all possible patterns for the machine.
  • provide errors for invalid pattern
• state.context suggestion and type validation

[ekweible]

Hey @sahandevs! I'd love to help out with this project, is there a particular area you could point me to as a good starting place?

[sahandevs]

Hi @ekweible! It would be awesome.

I've delayed this project but I will be back on it very soon. last thing I was working on was implementing the interpreter based on https://www.w3.org/TR/scxml (implemented part is here: https://github.com/sahandevs/xstate.dart/blob/master/packages/xstate/lib/src/interpreter/helpers.dart)

There are few todos there but the next thing i was going to work on was writing some test for the functions there. writing test for them should not be hard because they are bunch of independent function.

Thanks!