Functions add/diff/cmp for xtime

[Clive D.W. Feather]

In message <E0zQZGb-0003Om-00 at heaton.cl.cam.ac.uk>, Markus Kuhn
<Markus.Kuhn at cl.cam.ac.uk> writes
>Several commentors have expressed a desire to have a few basic
>predefined arithmetic functions on xtime values.
>
>I suggest to add the following three functions. These functions are so
>simple that I feel the easiest way of specifying their behaviour is by
>providing a sample implementation (i.e., using C as the specification
>language instead of English):

Sorry, but if they're that simple, why bother ?

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Clive D.W. Feather   | Regulation Officer, LINX | Work: <clive at linx.org>
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