The template parameter after a ! without parentheses is always 1 token, so it's never one of the first two interpretations.

Furthermore, the point is that often when writing generic code, you're not supposed to care what the `.d` means specifically. For example, an `InputRange` is defined to have `.front`, `.empty` and `.popFront` properties. Is `.empty` a member variable, function, or constant? Doesn't matter, as long as it results in a boolean.

This does require some getting used to. A common question from newcomers is how to explicitly spell out the type in a situation like this:

  import std.algorithm;
  void main()
  {
      auto x = [10, 20, 30].map!(x => x*2);
  }

While it's flexible, generic code is also complex. Many D standard library functions don't take a simple `string`, but a 'generic input range of a code unit'. (UTF-8, UTF-16, UTF-32). The resulting template machinery that this spawns is not pleasant to work with, so I understand your concern.

In my own D code, I often use regular arrays, foreach loops and if-statements instead of ranges, map and filter etc.