[LMH]BIGNUM format?

[Nyef]

Hello all.

Can I have a reality check? SSDN2, section 7.8.6.1 appears to say that 
BIGNUMs are stored in sign-magnitude format. Section 7.5.1 says that 
FIXNUMs are stored in 2s-complement format. ClTl says (I forget where) 
that LDB and DPB treat all integers as being in 2s-complement form.

My questions are:

    Are BIGNUMs -really- stored as sign-magnitude, and not 2s-complement?

    Do LDB and DPB behave, to a user, as if BIGNUMs are stored as 
2s-complement, as per ClTl, or does the abstraction break down there?

---------------------------
All programming can be viewed as an exercise.
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Alastair Bridgewater
e-mail: nyef@softhome.net