string.hpp

#ifndef HALCHECK_LIB_STRING_HPP
#define HALCHECK_LIB_STRING_HPP
 
#include <halcheck/lib/optional.hpp>
#include <halcheck/lib/type_traits.hpp>
 
#include <sstream>
#include <string> // IWYU pragma: export
 
namespace halcheck { namespace lib {
 
template<typename T, HALCHECK_REQUIRE(lib::is_printable<T>())>
std::string to_string(const T &value) {
  std::ostringstream os;
  os << value;
  return os.str();
}
 
template<typename T, HALCHECK_REQUIRE(lib::is_parsable<T>())>
lib::optional<T> of_string(const std::string &value) {
  T output;
  if (std::istringstream(value) >> output)
    return output;
  else
    return lib::nullopt;
}
 
lib::optional<std::string> getenv(const std::string &name);
 
template<typename T, HALCHECK_REQUIRE(lib::is_parsable<T>())>
lib::optional<T> getenv(const std::string &name) {
  if (auto value = lib::getenv(name))
    return lib::of_string<T>(*value);
  else
    return lib::nullopt;
}
 
}} // namespace halcheck::lib
 
#endif