export keyword

I was wondering if it'd be possible to add an export keyword. The reason is that in some JavaScript environments (hint hint, QtScript) people tend to require certain variable on the global scope. However, with the QtScript transition to V8, adding them to the "this" property will become a strict mode error if you don't use .call on a method, furthermore, many implementations don't posses a window-like object for the global scope.

The solution is to use the bare mode, but this isn't desirable. Instead I would propose the use of a special keyword, export.

a = 1
function randomNumber
 ...
export function eventAttacked victim, attacker
 ...

Might compile to:

var eventAttacked;
(function(){
 var a;
 eventAttacked = function (victim, attacker) { ... }
 function randomNumber () { ... }
 a = 1;
})();

[satyr]

adding them to the "this" property will become a strict mode error

You mean, the global object is frozen by default in that environment or something? Then you shouldn't be able to add global variables at all.

Running

<script>
"use strict"
var a
Object.freeze(this)
a = 1
</script>

on Firefox 11 gives Error: a is read-only.

"use strict"

function f () {
 this.q = 3;
}
f()
console.log(q);

ryan@R26695g /tmp $ node file

node.js:201
        throw e; // process.nextTick error, or 'error' event on first tick
              ^
TypeError: Cannot set property 'q' of undefined
    at f (/tmp/file:4:9)
    at Object.<anonymous> (/tmp/file:6:1)
    at Module._compile (module.js:432:26)
    at Object..js (module.js:450:10)
    at Module.load (module.js:351:31)
    at Function._load (module.js:310:12)
    at Array.0 (module.js:470:10)
    at EventEmitter._tickCallback (node.js:192:40)

In strict mode, you can't use this inside a function that's not a property of an object or called with the call method. The compiler wraps all your code in a function. Using the bare option defeats the safeguards.

Edit: Fixed

[satyr]

That's why we use .call(this) rather than just ().

@satyr
Sorry, maybe this(coco example) better shows my point:

"use strict"

this.x = 0
x := 3 # error
x = 4 # wrong
function e
 x := 2 # error
 this.x = 3 # error

Yes, it can be gotten around, but there are times when your environment does stupid things...

[satyr]

x := 2 # error

How?

this.x = 3 # error

Depends on how e is called.

Well, you have to remove the line marked #wrong to get the error. It's an "undeclared variable" error.

And I don't want to call e with funny calls every time, or bind every function in my code. I think an export would be a better solution, it's much less coding.

[satyr]

Assuming your intention at this.x = 3 is to change global x,

global = this
function e
  global.x = 3

is what you want.

Isn't that rather verbose?

And the issue is when I want to do that with a function.
do f
export function f

I would have to opt for the much less readable global.f = function ... for every function in my code which needs to be put on the global object.

[satyr]

less readable global.f = function

On top level that's merely @f = ->.

I'm not always going to be on the top level, if I want to reference it, I have to make the global object a variable, or call all my functions using .call @

global = this
@a = !(b, c) ->
 d
function e
 global.a 3, 6

I think export would be easier, it hurts my eyes to see functions assigned, especially with all that extra stuff...

Edit: Fixed.

[satyr]

@a = (b, c) !->

Try @a = !(b, c) ->.

The @a syntax does NOT hoist the functions. I have multiple files, and if I run code in part of it, a function may be in another file. It might end up below code that requires it. A good example is a util file: The functions have to be hoisted, if they aren't, they wont be available to most files. (those that start with anything which comes before u.)

I'm aware you don't like using multiple files and joining them. But we don't all live in a node.js environment where we can require the other files.

[satyr]

Ah, hoisting. In that case you do need export function I guess. See #116 and the mockup I wrote there.