Re: [Json] I-JSON Topic #5: Numbers

[John Cowan <[e-mail]>]

Carsten Bormann scripsit:

>    Software which implements IEEE 754-2008 binary64 (double precision)
>    numbers [IEEE754] is generally available and widely used.
>    Implementations which generate I-JSON messages MUST NOT assume that
>    receiving implementations can process numeric values with greater
>    magnitude or precision than provided by those numbers.  I-JSON
>    messages SHOULD NOT include numbers which express greater magnitude
>    or precision than an IEEE 754 double precision number provides,
>    for example 1E400 or 3.141592653589793238462643383279.  In
>    particular, an I-JSON sender MUST NOT expect a receiver to treat
>    an integer whose absolute value is greater than 9007199254740992
>    (i.e., that is outside the range [-2**53, 2**53], where ** stands
>    for exponentiation) as an exact value.
> 
> This then leads well into the next paragraph:
> 
>    For applications such as cryptography, where exact interchange
>    of much larger numbers is reasonably required, it is RECOMMENDED to
>    encode them in JSON string values.  This requires that the receiving
>    program understand the intended semantic of the value.

+1

-- 
John Cowan          http://www.ccil.org/~cowan        [e-mail]
So they play that [tune] on their fascist banjos, eh?
        --Great-Souled Sam