Fatal Exceptions

[OAGr]

• x Is new feature

Description of suggestion or shortcoming:

Maybe something like,

Common.raiseError(message: string)
or
Common.raiseErr(message:string)

This raises the error immediately.

Seems simple enough.

[berekuk]

In most languages, raise/throw is a builtin keyword. Tbh I'm not sure why, maybe because it's not an expression and most typed languages don't have Typescript's never?

In Squiggle it seems fine to make it an expression; if ... then ... else throw is useful, and statement-level throw is not useful.

[OAGr]

In most languages, raise/throw is a builtin keyword. Tbh I'm not sure why, maybe because it's not an expression and most typed languages don't have Typescript's never?

In Squiggle it seems fine to make it an expression; if ... then ... else throw is useful, and statement-level throw is not useful.

Sorry, I don't fully follow. Let's discuss tomorrow.

One nice thing about using a simple function is that it would be ~trivial to get started with.

[berekuk]

Sorry, I don't fully follow. Let's discuss tomorrow.

Second paragraph is not directly connected to the first, sorry for not making it clearer. I was just thinking out loud about the syntax.

In the approach where we add a keyword, there's the difference between:

f() = {
  x = 5
  throw "oops"
  ...
}

And:

f() = {
  x = checkCondition() ? 5 : throw "oops"
}

In the first example, throw is a statement. The theoretical benefit is that you don't need to pick a variable name.

In the second example, throw is an expression that's never used. (There's a parallel to Typescript here: in Typescript, if your function always throws, then its return type is never, and Typescript considers this type for several purposes, including the control flow analysis.)

Throw/raise is usually a statement, in Python or JS, but in current Squiggle there's no need for statement-level throw, because if you statement-level-throw then your function will always throw (we don't have early returns), and then you could just throw in the end expression.

[OAGr]

Common.throw(str)