Re: [boost] [boost::endian] Summary of discussion #1

Subject: Re: [boost] [boost::endian] Summary of discussion #1
From: Terry Golubiewski (tjgolubi_at_[hidden])
Date: 2010-06-04 08:28:37

Robert Stewart wrote:
> Terry Golubiewski wrote:
>>
>> It's easy for me to suggest that someone else should change.
>> But what would such a change look like.
>> How about this... (I've ignored alignment)
>>
>> namespace boost { namespace interface {
>
> boost::interface strikes me as a meaningless namespace.

I see several classes as having to do with message passing and communication 
interfaces.  endian, packed_int, bitfield, dispatcher, etc.
Perhaps just "comm" would be better?

>
>> template<size_t Bits,  endian_t Endian=native>
>> class PackedInteger {
>> public:
>>    typedef typename boost::int_t<Bits>::least value_type;
>>    static const endian_t endianness = Endian;
> [snip]
>>    PackedInteger(): { m_storage.fill('\0'); }
>>    explicit PackedInteger(value_type x) { store(x); }
>
> Why explicit?

Without the explicit, operations on PackedInteger, such as comparison, will 
have ambiguity.

>
>>    operator value_type() const { return retrieve(); }
>>    PackedInteger& operator=(value_type x) { store(x); }
>>    // All the usual integer operations go here.
>> }; // PackedInteger
>>
>> } } // boost::interface

The point of PackedInteger is to provide 3-, 5-, 6-, 7-byte integers.  It 
really doesn't have anything to do with endianess in intention.  However, 
when storing the values into memory, you have to decided which endian to 
use, of course.  I hastily picked the "PackedInteger" name because I believe 
it will be used by users that want the smallest integer that will meet their 
needs because they are space constrained, such as in messages.

>
> I don't understand the point of "packed" in the name.  I'd have expected 
> boost::endian to be what Beman has now minus arithmetic operators and then 
> boost::endian_integer to be derived from boost::endian with the arithmetic 
> operators.  That seems simple and obvious.  Have I missed something?