Concerning Time.TimeDiff

Malcolm Wallace
Mon, 16 Jun 2003 11:37:41 +0100

Simon Peyton-Jones wrote:
> The H98 Time module is probably broken in many ways.

I had a quick look at the official Haskell Libraries Report for the
Time module today, and the thing that struck me as most bizarre is
the sentence:

    "It follows RFC 1129 in its use of Coordinated Universal Time (UTC)".

What is so strange is the fact that the named RFC has absolutely
nothing to say on time representation formats, conversions, timezones,
and so on.  It is a specification of the NTP protocol, and concentrates
on the mechanics of transferring clock information from machine to
machine with corrections for skew and transport delays.

Much more relevant references for time representation would be ISO
8601, or RFC 3339, which *do* talk about calendar times, clock times,
and their conversion.  (Although I wouldn't be qualified to speculate
about how closely the Haskell Time module resembles either standard.)

Graham Klyne <> writes:
> I don't feel especially well-qualified, but if I can contribute in some 
> small ways...

A small surprise to me was that the editor of RFC 3339 "Date and Time
on the Internet: Timestamps" is one Graham Klyne, which may not be the
same person as you, but perhaps you are more qualified for the job of
proposing a new Time module than you admit...  :-)