Allowing optionals in @operator(construct)

[alexveden]

I'm fiddling with new @operator(construct), and it rejects to return optionals.

fn AstProject! AstProject.new_init(String proj_path, String stdlib_path) @operator(construct) {
    AstProject self;

}
>c3c 
 Error: The return type of a 'construct' method must be the method type, or a pointer to it. In this case 'AstProject' or 'AstProject*' was expected.

I think this makes no sense, because these are 2 equivalent initialization methods:

// current
AstProject proj;
proj.new_init(dir_name, "")!;

// the same effect with AstProject! return type 
AstProject proj = AstProject.new_init(dir_name, "")!;

[lerno]

This is deliberate. I understand it makes little sense in this case, but maybe we should just not have this @operator(construct). I deliberately didn't want: Url.parse(...) which would return an optional Url. For something like that url::parse is really correct.

Why is it optional in your case?

[alexveden]

Why is it optional in your case?

Maybe I wanted to do stuff which is error-prone:

1. path doesn't exist
2. parsing errors
3. something wrong with parameter validation?

Absence of optionals makes me to add another initialization method, let's call it load(). So the "constructor" will always succeed then, and initialization validation should be done with another method.

I don't have a strong opinion on this, and performance penalties for using optionals in constructors are also unclear.