Should we avoid assignment of derived types in robust programs?

[aradi]

As for the comment of @rouson : I absolutely agree, one should use allocatables, wherever it is feasible. Unfortunately, if you want to create an efficient list, allocatables are sometimes not enough. Think about a list containing large objects (arrays, other containers, etc.). You may wish the list to be able to deliver a pointer to a given list element, so that you can process the elements content without having to make a copy of it. As discussed in Enforcing target attribute for actual argument in TBP calls, it is basically impossible to obtain a reliable pointer to the component of a derived type, if it has no pointer components…