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V830. Decreased performance. Consider replacing the use of 'std::optional::value()' with either the '*' or '->' operator.
The analyzer has detected a block of code where the 'std::optional::value()' method is used to access the contents of an 'std::optional' object that is known to have been initialized.
Consider the following contrived example:
inline void LuaBlockLoader::loadColorMultiplier(
BlockState &state, const sol::table &table) const
{
std::optional<sol::table> colorMultiplier = table["color_multiplier"];
if (colorMultiplier != std::nullopt) {
state.colorMultiplier(gk::Color{
colorMultiplier.value().get<u8>(1),
colorMultiplier.value().get<u8>(2),
colorMultiplier.value().get<u8>(3),
colorMultiplier.value().get<u8>(4)
});
}
}This method adds an overhead for checking the contents: if an object of class 'std::optional' is found to be equal to 'std::nullopt', an 'std::bad_optional_access' exception will be thrown. If the object is known to be already initialized, the code can be simplified and speeded up by using the overloaded operator 'std::optional::operator*' or 'std::optional::operator->':
inline void LuaBlockLoader::loadColorMultiplier(
BlockState &state, const sol::table &table) const
{
std::optional<sol::table> colorMultiplier = table["color_multiplier"];
if (colorMultiplier != std::nullopt) {
state.colorMultiplier(gk::Color{
colorMultiplier->get<u8>(1),
colorMultiplier->get<u8>(2),
colorMultiplier->get<u8>(3),
colorMultiplier->get<u8>(4)
});
}
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