Optional.h

// =====================================================================================================================
// Copyright 2024 Medusa Slockbower
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//  http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// =====================================================================================================================
 
#ifndef OPTIONAL_H
#define OPTIONAL_H
 
template<typename T>
class Optional
{
public:
    using Type = T;
 
    Optional() : Data(), Valid(false) { }
    Optional(const Type& data) : Data(data), Valid(true) { }
    Optional(Type&& data) : Data(data), Valid(true) { }
    Optional(const Optional& other) = default;
    Optional(Optional&& other) = default;
 
    Optional& operator=(const Optional& other) = default;
    Optional& operator=(Optional&& other) = default;
 
    Type& operator=(const Type& data) { Data = data; Valid = true; return Data; }
    Type& operator=(Type&& data) { Data = data; Valid = true; return Data; }
 
    Type& operator+=(const Type& data) { assert(Valid); Data += data; return Data; }
    Type& operator-=(const Type& data) { assert(Valid); Data += data; return Data; }
    Type& operator*=(const Type& data) { assert(Valid); Data += data; return Data; }
    Type& operator/=(const Type& data) { assert(Valid); Data += data; return Data; }
    Type& operator%=(const Type& data) { assert(Valid); Data += data; return Data; }
 
    Type& operator<<=(const Type& data) { assert(Valid); Data <<= data; return Data; }
    Type& operator>>=(const Type& data) { assert(Valid); Data >>= data; return Data; }
    Type& operator|=(const Type& data)  { assert(Valid); Data |= data;  return Data; }
    Type& operator&=(const Type& data)  { assert(Valid); Data &= data;  return Data; }
    Type& operator^=(const Type& data)  { assert(Valid); Data ^= data;  return Data; }
 
    [[nodiscard]] bool operator()() const { return Valid; }
 
    operator Type&() { assert(Valid); return Data; }
    operator const Type&() const { assert(Valid); return Data; }
 
    Type* operator->() { assert(Valid); return &Data; }
    const Type* operator->() const { assert(Valid); return &Data; }
 
    Type& operator*()  { assert(Valid); return Data; }
    const Type& operator*() const  { assert(Valid); return Data; }
 
    void Reset() { Valid = false; }
 
private:
    Type Data;
    bool Valid;
};
 
#endif //OPTIONAL_H