On Thu, Dec 19, 2013 at 6:18 PM, Andrea Giammarchi <
andrea.giammarchi at gmail.com> wrote:

> Rick thanks but I wasn't strictly asking for solutions because I have one,
> I was rather pointing at the fact that there is no solution and by design
> we need to create garbage.
>
> Your last example talks itself ... why do we need to define another
> variable in that scope? That is annoying, imho ... I don't want define a
> `tmp` like variable per each const type I'd like to address down the road,
> you know what I mean?
>
> I cannot even drop that var, so that's a potential leak in the global
> scope/context if not loeaded through modules while I might want to define
> that constant globally (and maybe name-spaced, but that's not the issue
> here)
>
> IE11 ... I don't have it with me now, would this work nicely ? I think no
> :-(
>
> ```javascript
> let ES6_PROXY = true;
>  try {
>   new Proxy({},{});
> } catch(o_O) {
>   ES6_PROXY = false;
> }
> const ES6_PROXY = ES6_PROXY;
> ```
>

It doesn't matter if I ran this in IE11 today or Firefox/Chrome/whatever
when those implementations are updated: let and const bindings don't allow
_redeclaration_ of bindings that already exist in that scope.



>
> So const are not as simple and straight forward to be defined as it is in
> C or others and because these have been defined on top of `var` hoisting
> behavior.
>
> ```C
>
> #ifdef WHATEVER
>   static int const NAME = 1;#else
>   static int const NAME = 0;
>
> #endif
>
> ```
>
> Thoughts?
>

It's an invalid comparison, unless you're saying you want ifdefs in JS.
This is an apples-to-apples comparison:

C:

  if (1) {
    static int const A_VAL = 1;
  }
  printf("%d", A_VAL);

  // error: use of undeclared identifier 'A_VAL'

JS:

  if (1) {
    const A_VAL = 1;
  }
  console.log(A_VAL);

  //  'A_VAL' is undefined


Rick
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On Thu, Dec 19, 2013 at 6:18 PM, Andrea Giammarchi <andrea.giammarchi at gmail.com> wrote:

> Rick thanks but I wasn't strictly asking for solutions because I have one,
> I was rather pointing at the fact that there is no solution and by design
> we need to create garbage.
>
> Your last example talks itself ... why do we need to define another
> variable in that scope? That is annoying, imho ... I don't want define a
> `tmp` like variable per each const type I'd like to address down the road,
> you know what I mean?
>
> I cannot even drop that var, so that's a potential leak in the global
> scope/context if not loeaded through modules while I might want to define
> that constant globally (and maybe name-spaced, but that's not the issue
> here)
>
> IE11 ... I don't have it with me now, would this work nicely ? I think no
> :-(
>
> ```javascript
> let ES6_PROXY = true;
>  try {
>   new Proxy({},{});
> } catch(o_O) {
>   ES6_PROXY = false;
> }
> const ES6_PROXY = ES6_PROXY;
> ```

It doesn't matter if I ran this in IE11 today or Firefox/Chrome/whatever
when those implementations are updated: let and const bindings don't allow
_redeclaration_ of bindings that already exist in that scope.



> So const are not as simple and straight forward to be defined as it is in
> C or others and because these have been defined on top of `var` hoisting
> behavior.
>
> ```C
>
> #ifdef WHATEVER
>   static int const NAME = 1;#else
>   static int const NAME = 0;
>
> #endif
>
> ```
>
> Thoughts?

It's an invalid comparison, unless you're saying you want ifdefs in JS.
This is an apples-to-apples comparison:

C:

```C
  if (1) {
    static int const A_VAL = 1;
  }
  printf("%d", A_VAL);

  // error: use of undeclared identifier 'A_VAL'
```

JS:

```js
  if (1) {
    const A_VAL = 1;
  }
  console.log(A_VAL);

  //  'A_VAL' is undefined
```