v/vlib/v/tests/generics_with_pointer_index_test.v

module main

pub struct Vec[T] {
mut:
	data &T
	cap  int
	len  int
}

pub struct Iter[T] {
mut:
	v   &Vec[T]
	pos int
}

pub fn with_cap[T](cap int) Vec[T] {
	new_data := unsafe { C.malloc(cap * int(sizeof(T))) }
	unsafe { C.memset(new_data, 0, cap * int(sizeof(T))) }

	return Vec[T]{
		data: new_data
		cap: cap
		len: 0
	}
}

pub fn (ar &Vec[T]) iter() Iter[T] {
	return Iter[T]{
		v: unsafe { ar }
	}
}

pub fn (mut iter Iter[T]) next() ?&T {
	if iter.pos >= iter.v.len {
		return none
	}
	res := unsafe { &iter.v.data[iter.pos] }
	iter.pos++
	return res
}

pub fn (mut ar Vec[T]) push(elm T) {
	unsafe {
		ar.data[ar.len - 1] = elm
	}
}

struct Product {
	price f64
}

fn test_generic_with_pointer_index() {
	vec1 := with_cap[Product](5)
	println(vec1)
	assert vec1.len == 0
	assert vec1.cap == 5

	vec2 := with_cap[int](5)
	println(vec2)
	assert vec2.len == 0
	assert vec2.cap == 5
}