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Re: ordering indexing

Howard Chu writes:
> I never found any order-preserving hash functions that I
> could see being generally applicable here,

Are general order-preserving hash functions possible?
I don't see how, except the identify function and functions
that increase the length of the input string.

> but we could certainly do some indexing for specific
> syntaxes that represent timestamps and other limited
> size/range values. (I.e., we can crunch their normalized
> value directly into a 32 or 64 bit integer losslessly.)

Note that Generalized Time, the syntax of modifyTimestamp
etc., supports an arbitrarily large fractional part, which
you would need to append to the integer.

BTW, the full integer range of Generalized Time takes 39
bits, or 40-41 bits for quicker conversion.