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https://issues.apache.org/jira/browse/MESOS-2716?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14560479#comment-14560479
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Mark Wang commented on MESOS-2716:
----------------------------------
I see line 106 with this same functionality as getOrElse(), shall we just
rename it?
{noformat} // This must return a copy to avoid returning a reference to a
temporary.
T get(const T& _t) const { return isNone() ? _t : t; }{noformat}
> Add non-const reference version of Option<T>::get.
> --------------------------------------------------
>
> Key: MESOS-2716
> URL: https://issues.apache.org/jira/browse/MESOS-2716
> Project: Mesos
> Issue Type: Improvement
> Components: stout
> Reporter: Benjamin Mahler
> Assignee: Mark Wang
> Labels: newbie
>
> Currently Option only provides a const reference to the underlying object:
> {code}
> template <typename T>
> class Option
> {
> ...
> const T& get() const;
> ...
> };
> {code}
> Since we use Option as a replacement for NULL, we often have optional
> variables that we need to perform non-const operations on. However, this
> requires taking a copy:
> {code}
> static void cleanup(const Response& response)
> {
> if (response.type == Response::PIPE) {
> CHECK_SOME(response.reader);
> http::Pipe::Reader reader = response.reader.get(); // Remove const.
> reader.close();
> }
> }
> {code}
> Taking a copy is hacky, but works for shared objects and some other copyable
> objects. Since Option represents a mutable variable, it makes sense to add
> non-const reference access to the underlying value:
> {code}
> template <typename T>
> class Option
> {
> ...
> const T& get() const;
> T& get();
> ...
> };
> {code}
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