/* Copyright 2017, Ableton AG, Berlin. All rights reserved.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*
* If you would like to incorporate Link into a proprietary software application,
* please contact .
*/
#pragma once
#include
#include
namespace ableton
{
namespace link
{
// Subset of the C++ 17 std::optional API. T has to be default constructible.
template
struct Optional
{
Optional()
: mHasValue(false)
{
}
explicit Optional(T value)
: mValue(std::move(value))
, mHasValue(true)
{
}
Optional(const Optional&) = default;
Optional(Optional&& other)
: mValue(std::move(other.mValue))
, mHasValue(other.mHasValue)
{
}
Optional& operator=(const Optional&) = default;
Optional& operator=(Optional&& other)
{
mValue = std::move(other.mValue);
mHasValue = other.mHasValue;
return *this;
}
explicit operator bool() const
{
return mHasValue;
}
const T& operator*() const
{
assert(mHasValue);
return mValue;
}
T& operator*()
{
assert(mHasValue);
return mValue;
}
const T* operator->() const
{
assert(mHasValue);
return &mValue;
}
T* operator->()
{
assert(mHasValue);
return &mValue;
}
private:
T mValue;
bool mHasValue;
};
} // namespace link
} // namespace ableton