On Monday, 13 March 2017 at 21:33:56 UTC, Inquie wrote:
One can say that it is a useless feature because D doesn't have it... or one could say that D is useless because it doesn't have it. A nice balance is simply to say "It is a useful feature that has proven it's worth and it is time that D implements something like it". As D becomes more mainstream, these features will be requested. D should learn from other language/compilers just as other languages/compilers have learned from it. (it's a two a way street)
FYI: The "you must implement my feature request or D will never succeed" attitude is rather common and never helpful. Not to mention that such an argument would be demonstrably false: every popular language without the feature you want has apparently succeeded despite not having said feature.
When one had a shit load of types in a single file, it is nice to be able to fold them. It is also nice to be able to group them in some way(hence the question) and fold the group so that large chunks of the file can be visibly reduced.
If you have enough declarations in one file that they call for code folding, it may be better to move them to a separate module. Public imports and aliases allow doing this without breaking any code.
If you would like a way to achieve code folding without involving language constructs, I think the starting point would be your IDE/editor's D plugin vendor. Once implemented in one editor, the syntax could be implemented in others and be informally standardized.
I don't think that it would make sense to introduce it into the language syntax proper. The #region syntax in C# makes sense for C# because, as already mentioned, the language vendor is also the main IDE vendor; but also because C#, like Java, requires a lot more boilerplate - writing programs in C# is much more tedious without an IDE than with. This is not the case of D, which was designed to solve problems that would otherwise require boilerplate code in the language itself.
Generally speaking, I would recommend to simply avoid code folding altogether:
https://blog.codinghorror.com/the-problem-with-code-folding/
