This Package Is Amazing!

[kevinkhill]

I am blown away how fast I was able to get an initial working draft of my parser to run. Following the calculator example was invaluable to creating mine. Next step, variable substitution in expressions!

See the example on the README here

[bd82]

Note that from a performance perspective modeling the precedence in the parse tree is not the most efficient.
However you do not seem to have that many types of binary operators (currently) and maximum parser performance may
not be that important for you at this point (or ever...).

Additional information.

• chevrotain/examples/grammars/ecma5/ecma5_parser.js

  Lines 45 to 52 in e6c1f2a

  	// A.3 Expressions
  	// Note that the binary expression operators are treated as a flat list
  	// instead of using a new rule for each precedence level.
  	// This is both faster and less verbose but it means additional logic must be used to re-order the flat list
  	// into a precedence tree.
  	// This approach was used in the swift compiler.
  	// https://developer.apple.com/library/content/documentation/Swift/Conceptual/Swift_Programming_Language/Expressions.html#//apple_ref/doc/uid/TP40014097-CH32-ID383
  	// (scroll down to the note on binary expressions)

• The section is now called "Infix Expressions"

[bd82]

Yeah, the deep nesting due to modeling operator precedence as separate grammar rules can be very in-efficient.
It is unlikely to matter for you right now, just something to be aware of...

[kevinkhill]

Could you offer and guidance or resources on how to do variable substitutions? I had assignments working like #1=#3 but then getting my algebra to work right, I broke using variables on the right of the = 🤔

[bd82]

The problem is in the parsing phase or the interpreting phase?

[kevinkhill]

Interpreting. I think it's something with this and this and here

I'm not sure how to have it decide if it is assigning or looking up a value for that particular register. I had lookups working, but then assignment broke. Then I got assignments working, and then lookup broke. 🤦‍♂️

[kevinkhill]

I FIGURED IT OUT! 😁🎉🎊 I needed to expand into a value here instead of passing on the register.

[kevinkhill]

MVP 😁 https://fanuc-macro-b.netlify.app/

[bd82]

For example ECMAScript has an official test suite different implementations can run against

• https://github.com/tc39/test262

[kevinkhill]

The hardware interpreter is very deterministic. I'm confident in mocking out how it runs. I need to implement flow control and also figure out how to implement sub routines...

The react editor package I found, seems to have just the feature I need too!

I'm nowhere near this but a subset of the features is my goal. A basic editor that can step through a program

(it also helps I have access to manuals with ladder logic diagrams of the cnc machine)

[kevinkhill]

I guess the problem would be to ensure that it runs exactly the same on real hardware versus the interpreter...

I am already thinking about, different machines can create custom M or G codes too.

One manufacturer may have M50 be for the high pressure coolant and on another machine it's M88

[bd82]

I am already thinking about, different machines can create custom M or G codes too.

Ouch 😢

[kevinkhill]

That's more semantics thought, doesn't really affect the evaluation of a program. M codes make machine things happen