required vs optional

James Bonfield jkb at
Thu Feb 8 15:57:18 UTC 2001

On Thu, Feb 08, 2001 at 01:13:45PM +0000, Peter Rice wrote:
> How about:
> needed:y or needed:n
> default value would be assumed to be (parameter or required or optional)
> unless you think a default of Y is better.

Looking at this in more detail, I'm unsure of the default value. Specifically
"parameter or required or optional" implies that the default is no, as the
default for all three dependent variables is also no. A rough check implies
there are some 400ish items where none of parameter, require or optional are
defined (to be anything other than N or just the default).

Indeed it's only likely to be the case that we wish to set needed:n for an
option that has required or optional as an expression, which is probably only
a small percentage. I found roughly 50 expressions used in opt and req. If we
set the default of needed to be Y then most (but perhaps not all) of these
will need the req: expression duplicating in the needed: value.

Given that 50 is much less than 400 may I ask for the default to be needed:y?

I'm only thinking about producing less emboss changes and it has nothing to do
with the fact that dealing with a non-constant default value is a bit tricky
for me. :-)


James Bonfield (jkb at   Tel: 01223 402499   Fax: 01223 213556
Medical Research Council - Laboratory of Molecular Biology,
Hills Road, Cambridge, CB2 2QH, England.
Also see Staden Package WWW site at

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