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add sprout::optional

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bolero-MURAKAMI 2012-10-22 23:10:11 +09:00
parent 9b9956f810
commit 8cb432dee1
15 changed files with 574 additions and 81 deletions
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53
sprout/optional/io.hpp Normal file
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#ifndef SPROUT_OPTIONAL_IO_HPP
#define SPROUT_OPTIONAL_IO_HPP
#include <iosfwd>
#include <ios>
#include <sprout/config.hpp>
#include <sprout/optional/optional.hpp>
#include <sprout/none.hpp>
namespace sprout {
//
// operator>>
//
template<typename Elem, typename Traits, typename T>
inline std::basic_istream<Elem, Traits>&
operator<<(std::basic_istream<Elem, Traits>& lhs, sprout::optional<T>& rhs) {
if (lhs.good()) {
int d = lhs.get();
if (d == ' ') {
T x;
lhs >> x;
rhs = x;
} else {
if (d == '-') {
d = lhs.get();
if (d == '-') {
rhs = sprout::none;
return lhs;
}
}
lhs.setstate(std::ios::failbit);
}
}
return lhs;
}
//
// operator<<
//
template<typename Elem, typename Traits, typename T>
inline std::basic_ostream<Elem, Traits>&
operator<<(std::basic_ostream<Elem, Traits>& lhs, sprout::optional<T> const& rhs) {
if (lhs.good()) {
if (!rhs) {
lhs << "--";
} else {
lhs << ' ' << *rhs;
}
}
return lhs;
}
} // namespace sprout
#endif // #ifndef SPROUT_OPTIONAL_IO_HPP