add self-througt information about having assignment operators return a reference to *this
add self-througt information about having assignment operators return a
reference to *this

ASMlover/study,ASMlover/study,ASMlover/study,ASMlover/study,ASMlover/study,ASMlover/study,ASMlover/study,ASMlover/study,ASMlover/study