Uncaught Error: toAST() expects a succesfull MatchResult as first parameter, but the MatchResult is successful

[nailuj29]

I am creating an app that uses Ohm, and when trying to get an AST with the toAST function. However, I get an error stating toAST() expects a succesfull MatchResult as first parameter, but the MatchResult is successful I believe this is an error with the instanceof in the code, because semanticsForToAST fails similarly, and the MatchResult is successful

[pdubroy]

I wasn't able to reproduce this. Can you give me some more details about how are importing Ohm (e.g., require or import), and how you are running and/or bundling it?

It sounds like the problem is that there are two different instances of the module.

[nailuj29]

I am importing it using import and running it in a Vite with typescript.

[pdubroy]

@nailuj29 Can you show me exactly how you are importing and using it? If you give me the code it's much easier for me to try to reproduce.

Also, what does your tsconfig look like? That could make a difference.

[pdubroy]

Ok, I was able to reproduce the problem as follows:

1. Set up a new Vite project with npm create vite@latest, and chose "vanilla-ts" as the project type.
2. npm install -D ohm-js
3. Put the following code into main.ts:

   import ohm from 'ohm-js';
   import extras from 'ohm-js/extras';
   
   extras.toAST(ohm.grammar('G { start = }').match(''))
   

@nailuj29, is this similar to how you are using it?

[nailuj29]

Yes, that is what I am doing

[pdubroy]

@nailuj29 The issue is fixed now, and I've just published the fix in v16.3.1.