What are (were) the most difficult parts of D?

[Adam D Ruppe]

On Thursday, 12 May 2022 at 15:18:34 UTC, jmh530 wrote:
> What's the difference between a Type and Type Identifier?

The is expression roughly follows variable declaration style.

You write

int a;

to declare a new symbol named `a` of type `int`.

Similarly,

static if(is(T a))

declares a new symbol of type `a` if `T` is a valid type. (Of 
course, in this case, a and T are aliases of each other, so it 
isn't super useful, but in the more complex matches using the == 
and : operators, it might be different.)

The Identifier is optional.