Re: [Haskell-cafe] bitSize

On 29/08/2011 09:00 AM, Brandon Allbery wrote:

On Mon, Aug 29, 2011 at 03:40, Andrew Coppin mailto:andrewcoppin@btinternet.com> wrote:

I meant if you're trying to *implement* serialisation. The Bits class allows you to access bits one by one, but surely you'd want some way to know how many bits you need to keep?

I think that falls into the realm of protocol design; if you're doing it in your program at runtime, you're probably doing it wrong. (The fixed size version makes sense for marshaling; it's *dynamic* sizes that need to be thought out beforehand.)

If you're doing, say, cryptography, then thousand-bit random integers that need to be serialised are fairly common...

Sure, and there are encodings that let you do this without needing bitSize (BER). You need a word count, but that's usually part of the structure holding the integer.

OK. But since there's no way of getting a byte count for an Integer either...