Value.hpp
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#pragma once
// Distributed under the LGPL version 3.0 license. See accompanying
// file LICENSE or https://github.com/henryiii/CLI11 for details.
#include <string>
#include <memory>
#include "CLI/Error.hpp"
namespace CLI {
class App;
// Prototype return value test
template <typename T>
class Value {
friend App;
protected:
std::shared_ptr<std::unique_ptr<T>> value {new std::unique_ptr<T>()};
std::string name;
public:
Value(std::string name) : name(name) {}
operator bool() const {return (bool) *value;}
T& get() const {
if(*value)
return **value;
else
throw EmptyError(name);
}
/// Note this does not throw on assignment, though
/// afterwards it seems to work fine. Best to use
/// explicit * notation.
T& operator *() const {
return get();
}
};
}