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/*
* Copyright (c) 2019-2020, Sergey Bugaev <bugaevc@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
// This type implements the regular calculator
// behavior, such as performing arithmetic
// operations and providing a memory cell.
// It does not deal with number input; you
// have to pass in already parsed double
// values.
class Calculator final {
public:
Calculator();
~Calculator();
enum class Operation {
None,
Add,
Subtract,
Multiply,
Divide,
Sqrt,
Inverse,
Percent,
ToggleSign,
MemClear,
MemRecall,
MemSave,
MemAdd
};
double begin_operation(Operation, double);
double finish_operation(double);
bool has_error() const { return m_has_error; }
void clear_operation();
void clear_error() { m_has_error = false; }
private:
Operation m_operation_in_progress { Operation::None };
double m_saved_argument { 0.0 };
double m_mem { 0.0 };
bool m_has_error { false };
};
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