}
/** @brief Return the property associated to the provided key (or nullptr if not existing) */
-const char* PropertyHolder::get_property(std::string key)
+const char* PropertyHolder::get_property(const std::string& key)
{
if (properties_ == nullptr)
return nullptr;
}
/** @brief Change the value of a given key in the property set */
-void PropertyHolder::set_property(std::string key, std::string value)
+void PropertyHolder::set_property(const std::string& key, const std::string& value)
{
if (not properties_)
properties_ = new std::unordered_map<std::string, std::string>;