The APIs used in question aren't that accurate and DST is specified year by year and can change year by year (and have changed in the past). There is no fixed rule to state when DST is applied and when not (despite that those APIs use such makeshift rules). It is revised and applied year after year by profound research institues and announced when needed. Said this, usually you can indeed "predict" (and thus that is all what these API's actually do) when it will be applied where, but you will never be certain unless you look this up on those websites or other sources instead of relying on questionable "predicting" APIs.
Also, this still does not rule out the specific location input that you need from the user. As DST is not applied everywhere the same in the same timezone! And that is not something which those APIs take into account. The country location is very mandatory in reference to DST, thus not only the GMT offset is important.
Thus, this makes the circle full again and you'll come back to what I suggested before: Since you need the specific country to make this calculation accurate, you might as well dish everything from those "guessing" APIs and strait away look up country specific information on a trusted, always updated and well known online source.
This rules out the very common user input mistakes regarding GMT offsets, DSTs, etc. If the user wants to get it right he needs to look these things up on those very same sites for starters anyways. So why not skip all the possible error making and only ask for the country and look things up yourself instead of relying on the user to do it.
quote:
Originally posted by grinch
I also don't think that it's that difficult for someone to enter a few pieces of relevant time information. I didn't understand the analogy about software deadlines and software writers
I'm not talking about those who program the plugin but about those who use the plugin and thus need to fill out the variables.
As I said, when you search the forums you'll notice that such small and trivial information is in fact a very big issue to make it correct! And isn't so trivial anymore to get it right for the average person as you might think.
The ananlogy was exactly to show that even people who are extremely well programmers and thus should know about the ins and outs of this, even get it wrong sometimes and forget about or mix up different DST settings around the world when they announce a product of theirs to be released.
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