auto x = [1, 2]
x.push_back(3)
assert_equal(3, x.size())
assert_equal(3, x.back())
assert_equal(1, x.front())


load_module("stl_extra")

auto uint16v = u16vector();
uint16v.push_back(1u);
assert_equal(1, uint16v.front());


// push_back newly constructed return value that's non-copyable

var v = []
v.push_back(async(fun(){}))