C++ 20 has std::bit_cast<Integer>(const uint8*), so trivial to do no-convert endian functions safely based on casting the contigous bytes directly into the integral. byteswap isn't as great, because it bit casts to a temporary byte vector and then swaps the bytes and recasts. I was trying to avoid the allocation. This is just something that facilitates stream read/write little endianness conversions without intermediate buffering, since the bytes are read out of order.
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