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From Julian Feinauer <>
Subject Re: API Changes proposal
Date Mon, 03 Sep 2018 11:53:37 GMT
Hi Chris,

exactly, that was my point (sorry for writing it not out clearly).
We can do it that way the only thing we are "loosing" is to know whether bit was given by
the user explicitly or not.
I dont know if we need this after parsing is finished anymore.

So we can also do it your way.


´╗┐Am 03.09.18, 10:47 schrieb "Christofer Dutz" <>:

    Hi Julian,
    had to think a little to get your point ... but think I have ... In my example it's a
primitive "short" and in yours it's "Short" as nullable non-primitive-type.
    I don't technically prefer any of the two options. Physically the bit-offset of any non-bit
type is always 0 and not null (as in undefined) as every non-bit value always starts at bit
0 ... so for that reason I would prefer "short" with default 0 over the "Short" nullable version.
And this way we don't have to add null-checks in the code. But as I said ... that's a very
slight preference for that option.
    Am 03.09.18, 10:27 schrieb "Julian Feinauer" <>:
        Hi chris,
        I agree with your S7 field except for one little change.
        How do we proceed with the (optional) bit offset?
        I made it "Short" with the contract that null indicates no offset given.
        Another alternative would be to make it 0 as default or even Optional.
        I would prefer to have it nullable, what do you think?
        With the rest I'm fine but as this is part of our internal API now I think we also
have more freedom with evolving them as its not visible to users.
        For all other parts of your proposal +1 from me.
        Am 30.08.18, 10:15 schrieb "Christofer Dutz" <>:
            Hi all,
            especially @Julian ... could you please have a look at that I did with the S7Field
            Also there is a unit-test that should allow adding more statements and testing
everything is working ok [2].
            Does this match your idea on [3]? Looking at your addresses, I think that I might
have not quite got it ... is there always a "D" as first part after the "."? I always read
it as "DB" like Data Block ... but seeing DX and SW makes me wonder ... a quick check in my
TIA shows me the address of a Boolean field in a Data Block is "%DB1.DBX38.1" ... which one
is correct?
            As we're no longer constructing the objects themselves in the API, I took the
liberty to simplify the field objects so we now only have one type for S7.
            Am 28.08.18, 12:23 schrieb "Christofer Dutz" <>:
                Hi all,
                I just pushed changes to my API refactoring branch ... so far I only adjusted
the API module and added an example using the changed API.
                To have a look, please go to [1] ...
                General changes I implemented while working on the refactoring itself. I did
notice, that my current proposal "chris-2" did 
                Having to inject the type conversion code would have made it necessary to
inject a converter which didn't feel right. So I changed the API to be purely interface based.
                In order to be able to construct these objects I also added builders for them.

                I asked a few people here what they think, and most liked the simplicity and
didn't have any WTF experiences (Which seems to be a good thing as I did have to explain a
lot with the current API)
                Quick Feedback highly appreciated as I will start implementing DefaultPlcReadRequest
& Co (in driver-base ... together with the builders) after that I'll start migrating the
                Right now having a look a named example [1] would be a good start ... 
                Second would be a deeper look into the API module [2].
                Would be a shame to waste that time and effort if you think the changes suck
(or are less than optimal as non-Germans would probably call them ;-) ) .
                Am 27.08.18, 09:57 schrieb "Christofer Dutz" <>:
                    Ups ... after reloading .. I just saw Julians Proposal pop up ... haven't
looked into that ...
                    Will do that right away.
                    Am 25.08.18, 15:52 schrieb "Christofer Dutz" <>:
                        Hi Julian,
                        version 2 should now be quite different ... I started reworking my
original proposal and decided to revert that an start a second proposal.
                        My first did address some parts needing cleaning up, but I still wasn't
quite satisfied with it. So I did another more radical refactoring.
                        If you reload the second there should be a lot of differences.
                        I just hit "save" a few minutes ago however ... but now I'm quite
happy with it. So please have another look at the second proposal. 
                        And please, maybe add your own proposal ... my versions are just Brainstorming
from my side.
                        My favorite is currently "Chris' Proposal 2" ;-)

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