[fitsbits] further reopening of Public Comment Period on the CONTINUE convention

[Steve Allen]

On Thu 2016-04-21T01:21:52 +1000, Mark Calabretta hath writ:
> So it seems we now agree on creating two classes of string-valued
> keywords.  I would simply like to assign the labels "string" and "long
> string" to them.

When the WCS conventions were added to FITS it was not required that
all FITS readers be upgraded in order to make proper interpretation of
their full meaning, and it was not required to rewrite existing FITS
files which happened to have keywords matching the name in the new
standard.

Old FITS readers could still read new files with WCS keywords without
syntax error, but not get the meaning.
New FITS readers could still read old files with WCS keyword names
whose values were not conformed to the new requirements, and in that
case those new FITS readers would have to gracefully fail.

I am not seeing how the CONTINUE convention for string-valued keywords
is significantly different from previous changes to FITS conventions.
It still looks like the FITS community, readers and writers, can
coexist by following RFC Editor Jon Postel (RIP) advising all parties
"Be conservative in what you send, be liberal in what you accept"

--
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