Following on from today's call, the relevant piece of documentation is in http://icu-project.org/apiref/icu4c/classicu_1_1SimpleDateFormat.html

When numeric fields abut one another directly, with no intervening delimiter characters, they constitute a run of abutting numeric fields. Such runs are parsed specially. For example, the format "HHmmss" parses the input text "123456" to 12:34:56, parses the input text "12345" to 1:23:45, and fails to parse "1234". In other words, the leftmost field of the run is flexible, while the others keep a fixed width. If the parse fails anywhere in the run, then the leftmost field is shortened by one character, and the entire run is parsed again. This is repeated until either the parse succeeds or the leftmost field is one character in length. If the parse still fails at that point, the parse of the run fails.

So it seems that when the 'S' is next to other numeric units in the pattern, it will be subject to the above behaviour. Therefore:
- A pattern of HHmmssSSS with the input 112233123 will become 11:22:33.123 but the input 1122331234 will trigger an error.
- If the pattern includes a '.' to become HHmmss.SSS, I think the input 1122331234 will become 11:22:33.123 but I'll try and confirm.

Steve - Does that description match what you were seeing?

HTH,
Andy

Andy Edwards - IBM Integration Bus - DFDL

Email:	andy.edwards@uk.ibm.com
Snail Mail:	MP211, Hursley park, Hursley, WINCHESTER, Hants, SO21 2JN
Tel int:	247222
Tel ext:	+44 (0)1962 817222
Desk:	DE3 V17

The Feynman problem solving Algorithm
1) Write down the problem
2) Think real hard
3) Write down the answer
-- Murray Gell-mann in the NY Times

From: Steve Hanson/UK/IBM
To: Andrew Edwards/UK/IBM@IBMGB
Cc: DFDL-WG <dfdl-wg@ogf.org>
Date: 11/08/2015 12:53
Subject: Re: [DFDL-WG] OGF DFDL WG Call Agenda 2015-08-11 - agenda item on ICU 'S' symbol

Hi Andy

Your internal ticket #630 gave rise to external ticket http://bugs.icu-project.org/trac/ticket/10962, which claims to have fixed the API docs to clarify the behaviour.

fractional second - truncates (like other time fields)
to the count of letters when formatting. Appends
zeros if more than 3 letters specified. Truncates at
three significant digits when parsing.

S
SS
SSS
SSSS

2
23
235
2350

I can't see anywhere that addresses your point about about abutting versus non-abutting numeric symbols though?

As far as DFDL spec is concerned, this is what we say today:

fractional second (see note 1)

Number

SSS

235

There is no 'note 1', I think the note was made into a normal paragraph, which reads:

Any number of fractional seconds "S" may by specified in the pattern and accepted by implementations, but an implementation is free to represent a limited number of fractional seconds internally. Excess fractional seconds are truncated, not rounded up. At least millisecond accuracy must be implemented. Unlike other fields, fractional seconds are padded on the right with zero.

Regards

Steve Hanson
Architect, IBM DFDL
Co-Chair, OGF DFDL Working Group
IBM SWG, Hursley, UK
smh@uk.ibm.com
tel:+44-1962-815848

From: Andrew Edwards/UK/IBM
To: Steve Hanson/UK/IBM@IBMGB
Date: 11/08/2015 11:56
Subject: Re: [DFDL-WG] OGF DFDL WG Call Agenda 2015-08-11

Hi Steve

Re agenda item 2 and calendar patterns with 'S', this ICU ticket from last year might be relevant - https://icu.sanjose.ibm.com/gcoctrac/ticket/630. It seems that the error reporting may also depend on whether the pattern has 'S' on it's own or next to other numeric pattern entities. i.e. 'HHmmssS' is subject to length checking, but 'HHmmss S' is not, due to the space before the 'S'.

HTH,
Andy

Andy Edwards - IBM Integration Bus - DFDL

Email:	andy.edwards@uk.ibm.com
Snail Mail:	MP211, Hursley park, Hursley, WINCHESTER, Hants, SO21 2JN
Tel int:	247222
Tel ext:	+44 (0)1962 817222
Desk:	DE3 V17

The Feynman problem solving Algorithm
1) Write down the problem
2) Think real hard
3) Write down the answer
-- Murray Gell-mann in the NY Times

From: Steve Hanson/UK/IBM@IBMGB
To: dfdl-wg@ogf.org
Cc: Mike Beckerle <mbeckerle@tresys.com>, jorge.marizan@gmail.com
Date: 10/08/2015 18:29
Subject: [DFDL-WG] OGF DFDL WG Call Agenda 2015-08-11
Sent by: dfdl-wg-bounces@ogf.org

Please find agenda for call on Redmine at https://redmine.ogf.org/dmsf_files/13489?download=

Regards

Steve Hanson
Architect, IBM Data Format Description Language (DFDL)
Co-Chair, OGF DFDL Working Group
IBM SWG, Hursley, UK
smh@uk.ibm.com
tel:+44-1962-815848
-- dfdl-wg mailing list dfdl-wg@ogf.org https://www.ogf.org/mailman/listinfo/dfdl-wg

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