require = fn (ok: u1) void
{
    if (!ok)
    {
        #trap();
    }
}

[export] main = fn [cc(c)] () s32
{
    >string = "abc";
    require(string[0] == 'a');
    require(string[1] == 'b');
    require(string[2] == 'c');
    return 0;
}