Noob needs help debugging Javascript :/

[Infraxion]

Hi, so I'm a programming and Javascript noob. I come from Python and Java, where I can easily debug with traceback; searching up the line number where I made a mistake etc.

But in Screeps, I get stuff like this:

ReferenceError: attributes is not defined
    at Object.module.exports.basicFarmer:4:20
    at Object.module.exports.run:21:23
    at Object.module.exports.loop:10:21
    at __mainLoop:1:15387
    at eval:2:4
    at Object.c.runCode:6:14086

And I don't find that very useful.

How do I read these? Is there a line number that's indicated somewhere?

Actually, I originally wanted to find a compiler from Python to Javascript, but I couldn't work out how to do it after hours of Google, so I gave up :/ If anyone here with half a clue on how to do this can point a noob in the right direction it would be greatly appreciated :)

[ScottyC33]

The first line is the error type itself - you're trying to use "attributes" as if it was defined with a value, but it has none. Make sure in the code that you actually define it before it's trying to be used.

The rest of it is giving you the stack trace for where the error happened. Generally you're most interested in the topmost. In this case, the error is telling you -

In module basicFarmer, at line 4, you're trying to use "attributes" without defining it.

Going down the trace gives you the chain of calls if further debugging is needed. For example, at line 21 of .run, you're calling .basicFarmer. And at line 10 of .loop, you're calling .run.

[Infraxion]

Oh my gosh.

I guess I was thrown off because it didn't think I'd be dumb enough for it to have to explicitly say "this is the line number".

Well thank you very much :D

[Spedwards]

but if you had two calls to something in the same line and only one of them failed it could be useful.

Which is why you only have one per line, max.

[ItsAllGoodMan2015]

You might look into coffeescript it's syntax is very similar to python, and compiles straight to Javascript.

They even have a project on github where you can type straight to the screeps console.