src/util/io.h

/*
Copyright (c) 2019 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.

Author: Leonardo de Moura
*/
#pragma once
#include <lean/exception.h>
#include <lean/object.h>
#include "util/string_ref.h"

namespace lean {
extern "C" object* lean_io_error_to_string(object * err);

template<typename T> T get_io_result(object * o) {
    if (io_result_is_error(o)) {
        object * err_obj = io_result_get_error(o);
        inc(err_obj);
        dec(o);
        string_ref error(lean_io_error_to_string(err_obj));
        throw exception(error.to_std_string());
    } else {
        T r(io_result_get_value(o), true);
        dec(o);
        return r;
    }
}

inline void consume_io_result(object * o) {
    if (io_result_is_error(o)) {
        object * err_obj = io_result_get_error(o);
        inc(err_obj);
        dec(o);
        string_ref error(lean_io_error_to_string(err_obj));
        throw exception(error.to_std_string());
    }
    dec(o);
}

template<typename T> T get_io_scalar_result(object * o) {
    if (io_result_is_error(o)) {
        object * err_obj = io_result_get_error(o);
        inc(err_obj);
        dec(o);
        string_ref error(lean_io_error_to_string(err_obj));
        throw exception(error.to_std_string());
    } else {
        T r = unbox(io_result_get_value(o));
        dec(o);
        return r;
    }
}
}