What are the types of compiler errors?

[mhagmajer]

What are the types of errors that run and parse can throw?

[czerwinskilukasz1]

@mhagmajer
There are roughly 40 error instances in 20 files in askvm/, askjsx/ and askcode/:
https://github.com/xFAANG/askql/search?q=%22new+Error%22&unscoped_q=%22new+Error%22&type=Code

I would create a class hierarchy for them, e.g.:
Error, with subclasses

• ParseError
• CompileError
• RuntimeError

RuntimeError with subclasses, each error type being a separate subclass, e.g.:

• InvalidResourceRuntimeError for this error
• NotAnArrayRuntimeError for this and this error
• InvalidTypeRuntimeError for this error
  and so on

[mhagmajer]

@czerwinskilukasz1 why class hierarchy and not plan object with type? Maybe we should avoid OOP to make it easier to port AskVM to non-oop languages such as C

[czerwinskilukasz1]

@mhagmajer , I am fine with either, with a preference for classes, because they make the code more reusable and cleaner.

If we were to port AskVM to other languages, we would need much work anyway as we are using pretty many Typescript and Javascript features, like:

• instanceOf,
• Array.isArray,
• JSX templates,
• ES template literals,
• throw (including throw new Error)
  to name a few.
  So adding more classes for Errors would have small impact on the whole porting task.

[mhagmajer]

• instanceOf,
• Array.isArray,
• JSX templates,
• ES template literals,
• throw (including throw new Error)
  to name a few.
  So adding more classes for Errors would have small impact on the whole porting task.

These are all functions. I'm not sure how to reflect class hierarchy in AskScript while not introducing classes. Maybe with explicit prototypal inheritance?

[czerwinskilukasz1]

• instanceOf,
• Array.isArray,
• JSX templates,
• ES template literals,
• throw (including throw new Error)
  to name a few.
  So adding more classes for Errors would have small impact on the whole porting task.

These are all functions. I'm not sure how to reflect class hierarchy in AskScript while not introducing classes. Maybe with explicit prototypal inheritance?

I don't think there is prototypal inheritance in C.
How about we put all the thought regarding porting AskVM to C here: #143 ?

[mhagmajer]

@czerwinskilukasz1 prototypal inheritance is actually pretty easy to implement - you just need a pointer for the prototype. We use it for creating new environment (scope) when running functions