> I totally agree that we should have a consistent formatting for array index expansion.
> I had a look to the mjsonrpc code and I found the function parse_array_index_list(...) which does this job.

Yes, it is good to review this stuff. I think the json-rpc call should accept more array index patterns:

a[*] - whole array (even though it is unnatural use in javascript, we do not say "let a[*] = b[*]", we say "let a = b".
a[5-] - from 5th element to the end (in the case we do not know the length)
a[-10] - from first element to element 10 (this is same as a[0-10], but needed for consistency with previous case).

K.O.

> I have a similar function (adapted form previous code) in odb.cxx called strarrayindex(...) that is designed for the same "consistency" purposes between odbedit and sequencer.
> 
> Let me put few points that I noticed:
> - mjsonrpc has a very different way to write the full array (no indexes given) while currently sequencer requires "[*]" to do the same (otherwise it only changes the first value of the array)
> - currently the sequencer and the underlying ODB calls use two indexes (that are the same if you want to write only one key) so we will need a serious rewriting to allow something like "ODBSET array[1,3,5]"
> - if I correctly understood the code, mjsonrpc instead generates a list of indices and then calls an ODB write on each of them. That's not always a good thing, for example if you are writing an array of n parameters on a DAQ 
> board you will call the hotlink on that key n times
> - in addition to that the sequencer will also have to cope with variable-based indexes like "ODBSET array[$val]", but then how it should parse something like "[$a,1]" or "[$a*]"?
> 
> For the very first point I do not see a clean way to do this without breaking the compatibility of existing sequencers or having a difference between the two implementations.
> For the others I guess we can find a way out, however that's a major modification so I will put it on my todo list when I can find some free time.
> In any case I would propose to merge the two functions, so we have only to maintain a single implementation of the parsing.
> 
> I guess it's a good moment to brainstorm about that, let me know what you think
> 
> Marco
> 
> 
> > > The following all fail with "Cannot find ODB key "<key>""
> > > 
> > > ODBSET "/Detectors/Det*/Settings/Charge/Bias (V)[*]" 0
> > > ODBSET "/Detectors/Det*/Settings/Charge/Bias (V)[0-9]" 0
> > > ODBSET "/Detectors/Det*/Settings/Charge/Bias (V)[1]" 0
> > > ODBSET "/Detectors/Det*/Settings/Charge/Bias (V)*" 0
> > > ODBSET "/Detectors/Det*/Settings/Charge/Bias (V)" 0
> > > 
> > 
> > It would be cool if ODB pattern matching in the sequencer
> > were consistent with the ODB pattern matching in the json-rpc
> > interface for web pages:
> > 
> > https://midas.triumf.ca/MidasWiki/index.php/Mjsonrpc#Supported_array_index_syntax
> > 
> > K.O.