jQuery error messages are excessive / counter-productive (perhaps a more general problem)

[jcward]

Given: A core value of a typed language like Haxe is good compiler error messages that help the programmer quickly identify mistakes.

A simple typo in the JQuery helper function results in 32 lines of useless "overload resolution failed" error messages before simply pointing out: Unknown identifier : my_typo

I don't know technically whether there's a general way the complier could improve these situations (or whether they occur for other popular libs/externs), or if the JQuery macro / extern definitions themselves are to blame, but both are (currently) in this repo.

Thought: Would an undefined check in the macro here, before the return statement, head off all these overload resolution errors (presumably from the extern)?

---

Here's a sample: https://try.haxe.org/#c0a5c

import js.jquery.Helper.J;
import js.Browser.*;

class Test {
    static function main() {
        trace("Haxe is great!");
        var my_div = document.createElement('div');
        
        // A simple typo results in 35 lines of confusing error
        // message, burying the error: Unknown identifier : my_typo
        J(my_typo).css('color','#fff');
    }
}

Spotting the relevant error message is harder than finding a needle in a haystack:

[jcward]

Interesting, simply trying to type the incoming expressions does, indeed, cause the compiler to fail with a nice, single error message. But will this have any other unexpected consequences?

	macro public static function J(exprs:Array<haxe.macro.Expr>) {
		for (e in exprs) haxe.macro.Context.typeof(e);
		return macro new js.jquery.JQuery($a{exprs});
	}

Error message simply becomes:

Test.hx:11: characters 10-17 : Unknown identifier : my_typo

[nadako]

A reduced example would be:

extern class J {
	@:overload(function(s:String):Void {})
	public function new():Void;
}

class Main {
	static function main() {
		new J(my_typo);
	}
}

So there's no help applying a hack to a macro, the compiler should simply filter out overload resolution errors when there's Unknown_ident or similar error.

[jcward]

Awesome, thanks @nadako, I had a hunch perhaps there was a more general fix. 👍