ISO 8601 assumption

Jesper Nørgaard jnorgard at
Fri Oct 6 05:58:32 UTC 2000

I even disagree about the assumption that yyyy-mm-dd is unambigous, because if the month number and the day-in-month number can be confused, they surely will according to Murphy's law, e.g. some people will create yyyy-dd-mm dates just as surely as they will create mm-dd-yyyy dates.

I have always liked another standard, the yyyy-mmm-dd standard, because no matter how you interchange the elements, they are always unambigous, e.g. 08-OCT-2000, AUG-10-2000 or even 2000-01-JAN can't be misinterpreted simply because each element has different length. Unfortunately this standard has not gained much recognition, perhaps because it assumes english as the base language for the acronyms (JAN, FEB, MAR ...).

That humanity has still not come up with a completely unambigous date format which is generally accepted, really shows how much IT is still in it's infancy. From a technical point of view it is a trivial problem, but of course it should be human-readable. Another similar problem is the myriad of ambigous ways that we identify a computer user, without really getting certain WHO it is. I am talking about those 40+ different account names with corresponding password I'm keeping in a password keeper program, about all the different finger print, eye scanner  systems etc. that have been developed isolated, still without reaching a simple way to identify a computer user. Maybe in 20 years I will laugh of this mail because the solution has been implemented everywhere, but at the moment I think it is a big problem that is the real reason why e-commerce is still not raving off with millions of computer based transacions. Who are you giving credit? The 5-year old son of a well-known user? You'll have to guess.

Meanwhile, why yyyy-mmm-dd or some other completely unambigous date format could not become international standard is beyond me. We *could* begin by defining an unambigous standard for the tzdata list though. I realize of course that isolated seen tzdata is already unambigous because it is already stated *somewhere* which standard has been used.

My apologies for drifting a bit away from the original issue.

Jesper Nørgaard
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From: 	Garrett Wollman[SMTP:wollman at]
Sent: 	Jueves 5 de Octubre de 2000 6.10
Cc: 	Time Zone Caballeros
Subject: 	Re: proposed tz changes for Paraguay, Brazil, Wayne County, etc.

<<On Thu, 5 Oct 2000 18:47:32 +1100, Alex LIVINGSTON <alex at> said:

> If hyphens are used to separate the numbers, the assumption is (I 
> hope) that ISO-8601-style decreasing-magnitude notation is being 
> used.

No, no such assumption can be made.  Using hyphens to separate
elements in a date was well-established practice in the United States
before there ever was an ISO.  The only time you can assume that a
date is written in ISO 8601 format is when the full yyyy-mm-dd form is


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