$ whois d

D

first released in 2001 · by Walter Bright, Andrei Alexandrescu

$ guessprog --inspect d

year: 2001
paradigm: multi paradigm
family: c like
memory: hybrid
binding: static
safety: strong

D(7)

AUTHORS: Walter Bright, Andrei Alexandrescu
HISTORY: Walter Bright, who had written the first native C++ compiler (Zortech C++), began designing D in 1999 at his company Digital Mars as a re-engineering of C++ without its accumulated complexity. The first version was released in 2001. Andrei Alexandrescu later joined the design, and together they shaped D2, with stronger support for generic programming, immutability and compile-time function evaluation, which lets ordinary functions run inside the compiler.
USAGE: A niche systems language with a small, dedicated community, used by some companies for high-performance backend, finance and tooling work. It has three compilers: DMD, LDC (LLVM-based) and GDC (part of GCC).
SEE ALSO: D on Wikipedia ↗

$ cat ranges.d

import std.stdio, std.algorithm, std.range;

ulong fib(uint n) { return n < 2 ? n : fib(n - 1) + fib(n - 2); }

// Computed by the compiler, not at run time
enum fib20 = fib(20);

void main() {
    writeln("fib(20) = ", fib20);
    iota(1, 20)
        .filter!(n => n % 3 == 0)
        .map!(n => n * n)
        .each!writeln;
}