Re: [Pvmanager-devel] Data conversion from scalar to array

[Carcassi, G. <car...@bn...>]

Based on feedback and further thinking, here's where I am right now:

 

* Data conversion should not be in the datasource. It's a mess
otherwise: people implementing the epics3, epics4, simulation or
whatever implement thing differently... (There are caveats in term of
performance optimization, but I don't think they change the general
rule)

* What is a valid conversions is somewhat specific to the task at hand,
so it is better to be explicit. Explicit should not mean onerous. So:

vDouble("mypv") - means a VDouble and only a VDouble

numericScalar("mypv") - means any scalar value and is converted to a
VDouble

numericValueOf("myPv") - means any scalar, array or multichannel array,
take the first element and convert to a VDouble

all return VDouble and the user can choose what is more appropriate.

 

So, PVManager user side can choose, DataSource implementor only returns
the native type, those operators take care of making the client-side
conversion so that it always works regardless of implementation. And
everybody is (hopefully) happy...

 

Gabriele