On Oct 18, 2017, at 8:58 AM, Daniel Ford <dfnojunk@gmail.com> wrote:
... So I went looking for a place where these quadruple rules might apply. My first search was for Baghdad, which turned up another issue in the current (2017b) Asia file that doesn't quite make sense to me. From line 1146...
Rule Iraq 1986 1990 - Mar lastSun 1:00s 1:00 D # IATA SSIM (1991/1996) says Apr 1 12:01am UTC; guess the ':01' is a typo. # Shanks & Pottenger say Iraq did not observe DST 1992/1997; ignore this. # Rule Iraq 1991 2007 - Apr 1 3:00s 1:00 D Rule Iraq 1991 2007 - Oct 1 3:00s 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Baghdad 2:57:40 - LMT 1890 2:57:36 - BMT 1918 # Baghdad Mean Time? 3:00 - +03 1982 May 3:00 Iraq +03/+04
Because there is no *current* RULE for Baghdad (the last expired 2007 according to the table), I assume that DST no longer occurs there.
I would not call that "no current rule". The lines in the rule files specify offsets, and the time when that offset goes into effect. For any given time, the offset that applies is the one specified by the most recent prior effective-time. Your conclusion looks correct to me: since the most recent time change established standard time (on 10/1/2007) has not applied since then. paul