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Comment by WalterBright | Hacker News Reader

The neato thing about obj.foo() goes even further. Ever seen code like:

    a(b(c(d(e),3))

? Not very readable. UFCS (Universal Function Call Syntax) enables it to be written as:

    e.d.c(3).b.a();

Reading it flows naturally left-to-right.

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Thanks Walter, that's a great example and I like that, because parens are optional, it could also be written as

    e.d.c(3).b.a

which is even cleaner.

For those who are thinking UFCS is a trivial detail, consider that the shell and some other languages have pipe operators (|>) to make the code flow intuitively the same way as the data.

In my opinion, in a C-like language, managing to squeeze so much functionality out of the '.' operator without any downsides is the mark of a well thought out, elegant language.

Thank you for creating D.

It is cleaner, but unfortunately it is not explicit. It is a function or a variable? I used to love those things until I noticed its defects.

For example, in C++, a = b can invoke anything. Not sure it is a good idea (except for generic code, there it is useful).

Zig has a philosophy of nothing hidden that I think it is mostly good.

That said, I find D a very nice language, the only problems are:

1. small ecosystem 2. last time I tried, packaging of download and use was... improvable.

Isn't it amazing how the . operator can cleanly replace :: and -> too?

Absolutely! Speaking of operators, out of curiosity, what's the reason for using '!' with templates?

Naively, I would think that making template instantiation look the same as a function call would be a desirable feature, with ambiguous calls needing to be resolved by the user.

Not many characters left in ASCII. Reuse of an existing operator almost required. Binary operators cannot be use as it would be grammatical ambiguous and would need resolution at the semantic pass which is a big no-no (that's why C++ is so slow at compiling, it cannot be parsed without semantic analysis). This left only the two exlusively unary operators !, ~. As ~ was repurposed for string concatenation, only ! remained.

    templ!thing(a,b)

I would have thought that templ(thing)(a,b) would have been a good solution, as it is what is used in the declaration/definition side of templates, but this would have made removing redundant () not possible in UFCS expressions.

i would have preferred:

    templ<thing>(a, b)

because with that:

    templ!thing(a, b)

is it a function?, or are you calling thing's function?

you can do:

    templ!(thing)(a, b)

but did you mean?:

    templ!(thing(a, b))()

i personally always use !(), no matter what, and it's annoying to type, i don't want to waste time constantly trying to figure out what is what, it's mentally draining

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