Jason Rhinelander 546f6fce1a Add an ability to avoid forcing rvp::move ... Eigen::Ref objects, when returned, are almost always returned as rvalues; what's important is the data they reference, not the outer shell, and so we want to be able to use `::copy`, `::reference_internal`, etc. to refer to the data the Eigen::Ref references (in the following commits), rather than the Eigen::Ref instance itself. This moves the policy override into a struct so that code that wants to avoid it (or wants to provide some other Return-type-conditional override) can create a specialization of return_value_policy_override<Return> in order to override the override. This lets an Eigen::Ref-returning function be bound with `rvp::copy`, for example, to specify that the data should be copied into a new numpy array rather than referenced, or `rvp::reference_internal` to indicate that it should be referenced, but a keep-alive used (actually, we used the array's `base` rather than a py::keep_alive in such a case, but it accomplishes the same thing).		2017-02-24 23:19:50 +01:00
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pybind11	Add an ability to avoid forcing rvp::move	2017-02-24 23:19:50 +01:00