[MITgcm-devel] check for pkg parameter files (data.ThiPKG)

[Jean-Michel Campin]

Hi,

Generally, for most packages, in order to use "thisPKG", a user
will have to remember 3 things: compile it (packages.conf), 
switch on the logical "useThisPKG" in data.pkg, and provide a 
parameter file "data.thisPKG".
if the user just do 2 of the 3 steps but forgot the 3rd one:
 - compile + useThisPKG=T but no data.thisPKG           --> stop cleanly
 - useThisPKG=T (+ data.thisPKG exist) but not compiled --> stop cleanly
 - compile thisPKG + data.thisPKG exist but useThisPKG=F --> nothing
In the 1rst 2 cases, there is a clear error message, but in the 3rd case
there is no specific warning that thisPKG is not used.

I am going to try to add a (weak, in lower-case) warning for the case where
pkg/diagnostics is compiled and data.diagnostics exist but useDiagnostics=F. 

I am not sure this is really useful; for now, it's just 1 pkg,
so would not be too much pain to remove this (just 1 file).
Any suggestion is welcomed.

Cheers,
Jean-Michel