[swift-evolution] [Idea] Distinguishing code comments from text comments.

[Magnus Ahltorp]

> 29 Aug. 2016 22:16 DifferentApps info <andre_ponzo at differentapps.com> wrote:
> 
> The advantage is that you do not need to define a conditional flag for the #if.

The good news is, you don't.

#if false
  print("Disabled code")
#endif

which is a time-tested way of writing C code (using #if 0).

From the Swift changelog, where they even call it an idiom of C:

2014-04-30
[…]
* You can now use the `true` and `false` constants in build configurations,
  allowing you to emulate the C idioms of `#if 0` (but spelled `#if false`).

One pattern I use all the time, both in C and in Swift, is this:

#if false
<experimental code>
#else
<old code>
#endif

which makes it possible to switch between the implementations quickly, something you cannot do with the proposed syntax.

> Code disabling (with /{...}/) is a tool useful when developing algorithm, and disabled code should not be aimed to remain definitively in a Swift file.

Which is in no way dependent on if you use the proposed syntax, traditional comments, or conditional compilation.

/Magnus