Zig generic Matrix struct

zig_matrix.zig

pub fn main() void {
    const foo = Matrix(f32, 4, 4).identity();
}

fn Matrix(comptime Scalar: type, comptime Width: usize, comptime Height: usize) type {
    return struct {
        const Self = @This();

        pub elems: [Width * Height]Scalar,

        pub fn identity() Self {
            comptime {
                var x: usize = 0;
                var y: usize = 0;
                var mat: Self = undefined;
                inline while (y < Height) : (y += 1) {
                    inline while (x < Width) : (x += 1) {
                        comptime const idx = y * Width + x;
                        mat.elems[idx] = if (x == y) 1 else 0;
                    }
                }

                return mat;
            }
        }
    };
}