struct ast *parse_simple_command(void)
{
    struct list *cmd_elements = NULL;
    char *token = pop_token();
    if (token == NULL) // just in case ?
    {
        puts("Internal error: cannot get the following token");
        return NULL;
    }

    while (token != NULL && !isterminator(token[0]))
    {
        cmd_elements = list_append(cmd_elements, token);
        token = pop_token();
    }

    if (token == NULL)
    {
        puts("Internal error: cannot get the following token");
        return NULL;
    }

    struct ast *result = ast_create_cmd(cmd_elements);
    return result;
}

struct ast *parse_if_rule(void)
{
    return NULL;
}

struct ast *parse_shell_command(void)
{
    return parse_if_rule();
}