ElementType

The element type of R. R does not have to be a range. The element type is determined as the type yielded by r.front for an object r of type R. For example, ElementType!(T[]) is T if T[] isn't a narrow string; if it is, the element type is dchar. If R doesn't have front, ElementType!R is void.

Examples

import std.range : iota;

// Standard arrays: returns the type of the elements of the array
static assert(is(ElementType!(int[]) == int));

// Accessing .front retrieves the decoded dchar
static assert(is(ElementType!(char[])  == dchar)); // rvalue
static assert(is(ElementType!(dchar[]) == dchar)); // lvalue

// Ditto
static assert(is(ElementType!(string) == dchar));
static assert(is(ElementType!(dstring) == immutable(dchar)));

// For ranges it gets the type of .front.
auto range = iota(0, 10);
static assert(is(ElementType!(typeof(range)) == int));

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