Using unordered_set may cause errors about orangec

[LADSoft]

there was a problem with the 'hook' operator: when one of the results was nullptr the overall type would become nullptr instead of the type of the other result. This cascaded into an incorrect selection for the overload of unique_ptr::reset and caused the unordered set initialization process to crash.

[tenk-a]

smp.cpp was compiled with v 6.0.24.1. (smp 2, smp 3 is still)

[LADSoft]

sorry I totally missed that there were three issues. On the second, there was a problem with declaring class member functions outside a specialization of the class. I fixed the third as well

[tenk-a]

v 6.0.25.1, smp2.cpp can be compiled. smp3.cpp no longer abort.
Thank you