Szathmáry László honlapja @ DEIK | DLang / Python's range()

See also std.range.

(1) iota()
def main(): print(list(range(5))) # [0, 1, 2, 3, 4] print(list(range(5, 10))) # [5, 6, 7, 8, 9] print(list(range(5, 15, 2))) # [5, 7, 9, 11, 13] print(list(range(10, 0, -2))) # [10, 8, 6, 4, 2]	import std.stdio; import std.range; // iota() void main() { writeln(iota(5)); // [0, 1, 2, 3, 4] writeln(iota(5, 10)); // [5, 6, 7, 8, 9] writeln(iota(5, 15, 2)); // [5, 7, 9, 11, 13] writeln(iota(10, 0, -2)); // [10, 8, 6, 4, 2] }
We convert the range to a list to make it printable.	`writeln()` can print a range, thus converting a range to an array (just for printing) is not necessary.

walkLength

See https://dlang.org/phobos/std_range_primitives.html#walkLength

To figure out the number of elements in a range, use walkLength(). If length() doesn't work, try this :)

(2) walkLength()

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

void main()
{
auto r = iota(10).filter!(x => x % 2 == 0); // it's a range

writeln(r); // [0, 2, 4, 6, 8]

// writeln(r.length); // Error

writeln(r.walkLength); // 5
}