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foreign

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good morning again everyone welcome back

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to the last session before lunch

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um we're going to continue linking

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python with other kinds of language with

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a talk by David Bowe and David's a

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software engineer and former University

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tutor

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um in his spare time David mentors the

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drop bears a first first first

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robotics competition team and helps to

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maintain robot pie a project to bring

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python to the FRC and I'm a little bit

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worried about robotic drop bears so

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we'll see if you've got them covered

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um thanks very much David give him a

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welcome

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[Applause]

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I feel like this is a bit of an

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interesting duel to the the previous

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talk because I'm about to do basically

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the exact opposite sort of

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um but let me set the scene a little bit

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so perhaps you have a somewhat large C

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plus library that you want to ship to

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python users but you don't

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want to put in a lot of work into doing

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that

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um or maybe you've written a a c plus

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library for

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perhaps for performance reasons and you

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want an easy way to be able to use it

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from python

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um so this is the sort of problem that

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we had uh it's robot Pi which is a

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project to bring python to the first

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robotics competition we have to deal

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with some reasonably large libraries and

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both open and closed source and this is

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because they do actually have to

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communicate with Hardware so it needs to

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be able to call native code at some

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point and to give you an idea of what

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the first robotic competition is this is

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teams of high school students with adult

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mentors building 56 kilo robots to play

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a sporty kind of game

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um so you can see an example there

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they get a new challenge each year to

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try to keep it interesting

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um so yeah let's get into it uh so

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one option that you might have is Swig

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or the simplified wrapper and interface

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generator

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um

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this lets you uh

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take some C or C plus plus and output a

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bunch of bindings for

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multiple different languages and this is

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one of the the oldest ones that I could

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find

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um

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and the fact that it works across so

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many different languages is probably a

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testament to how mature it is

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and

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they do intentionally try to keep it as

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simple as possible so this is a very

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simple example uh where you can take a

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take your header file for your library

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and you just you can just include it

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um and you might want to ignore some

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things maybe

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um because they're convenient for

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C C plus plus but it doesn't really make

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sense for python

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um

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one of the other uh popular open source

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projects is sheboken which is one of the

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underlying libraries used by QT for

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python or you if you've been around for

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a while you've been using QT you might

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know it as Pi side that

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Pi side projects uh eventually became

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adopted by the QT project and is now

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like the quote-unquote official bindings

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for QT

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and they use some XML to configure

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which kind of looks like this

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uh which this is this is an example I

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pulled straight from their docs it is a

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little bit intimidating though so I'm

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going to break it down a little bit and

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so here we have our first class that

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that we're binding to on the left hand

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side is the XML the right hand side is

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the C plus definition it's a declaration

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for it sorry

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um you can see we have two methods in

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there

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um but the XML only talks about one of

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them so by default uh all methods are

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exposed to python

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and

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here we have to if we say that we want

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some special handling for this clone

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method uh particularly we modify what it

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calls argument index zero that's the

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return value of of that method

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and here we're actually saying that uh

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the bindings should not uh destroy the

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object and it should instead let C plus

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plus deal with the memory management

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because we get a pointer so so it

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doesn't actually know

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necessarily how to handle that

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and then we have this other class

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there's a whole bunch of more methods

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but what's interesting in the the the

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bindings here is that we also have a

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property that we can Define so you can

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just you know do truck dot arrival

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message and instead of having to call

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get a rival message and and set a rival

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message to set it

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um and and then we have a similar thing

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with memory management

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we

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and argument index one actually refers

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to the argument this time so

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um

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uh and this takes us to the

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underlying library that we use uh we

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chose to use which is pi bind 11. it's a

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c plus header only Library so it's

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pretty easy to pull into a c plus

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project

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and it lets you build a module uh and

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you declare everything that you want to

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expose to python in a c plus file

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um and it does let you also

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depend on classes from different Pi bind

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11 modules that you've and that have

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been built

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um I believe shaboken does support this

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as well but I haven't actually

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use that all that much uh let me know if

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if that's wrong but we'll see why this

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is important a little bit later

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um here is an example of Pi bindle of

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what pi by 11 looks like

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so on the left hand side I have my C

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plus code to to generate to have these

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bindings

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um first we say that we're building an

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a511 module and then next here is our

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module name so so to import this module

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from my python code I would you know say

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import python EU example

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and then M here is a variable name in

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the C plus code to say this is the

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module that I'm putting together so the

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first thing that we have here is we

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Define and add thing specifically the

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where putting the ad

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function that you can see on the right

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hand side that declaration and we're

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exposing that to python

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and then we have this pet class

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so we say I want a class called pet

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we put that on the module and it

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corresponds to the C plus plus pet class

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that you can see

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so you so we

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this first line here with the the pi

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pack in it

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that corresponds to the Constructor here

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and then we

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bind the set name get name methods

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fairly straightforward

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and then we can also declare a property

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just like you could in chibokin

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so

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this

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kind of takes us into a journey that we

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went through with a couple of our

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earlier approaches to

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to generate All That C plus plus code

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that we would have to write otherwise

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um

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because

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we have some fairly large libraries

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right

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um so the

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first example that I I'll show here

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is a involves a vendor library that

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provides a c interface

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so we ended up building a library that

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can take a c plus header file

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it pauses it using a pure python C plus

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plus parser

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there were good reasons for this

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um

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but this Library lets us

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generate lit literally whatever we want

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from a c plus header

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so it takes in some python code and a

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bit of yaml configuration

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that's provided to that python code and

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then puts it into a ginger to template

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um

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so

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here's an example of what that sort of

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looks like on the left I have some yaml

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um

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so each top level entry is each function

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that we want to bind to

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uh you'll you'll notice on the right

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hand side each of these take this handle

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pointer so we decide to abstract that

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away and put it in a c plus so that we

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don't have to deal with it

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um and then you can see here's something

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interesting

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we provide we can set

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some default values for for some of

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these parameters and

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you might notice that that's a default

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value in the middle here that's because

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in our python code we had set a

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global default for for parameters called

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timeout Ms to zero

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this is what the

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ginger 2 template looks like to generate

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the C plus plus classes

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um it's scary that if you actually want

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to read the code there's a link there

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but this is then the template for the pi

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bind 11 code

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um

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feel like you probably get the idea so I

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won't show you the pipe the python code

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and that that first that first

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preprocessors uh it so

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but yeah

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so

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next example

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uh we ended up getting a vendor Library

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uh that's only exposed a an

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object-oriented uh C plus plus interface

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uh so luckily we already had all this

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generation code from that previous

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library that that we built

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so we decided to reuse some of some of

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it

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um

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so yeah similar sort of setup uh with

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the same libraries but different python

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code and and the yaml looks a little bit

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different

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so here we have this

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uh C plus plus class at the top

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and then we declare a few different

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methods

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um you uh you might notice if you look

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at the right hand side there are two

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methods with the exact same name

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this is called overloading and C plus

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plus

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where you can

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essentially uh

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end up calling a different function

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depending on what

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parameters you pass in

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um but in Python this kind of ends up

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looking a little bit ugly so what we did

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was we actually ignored this first

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method and then we set the a default for

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the second overload because

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we dug into it and it turns out that the

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first overload actually just delegates

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to the second

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I'll also note here you might notice

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that these method names are Pascal case

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so we turn them into camel case this is

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because we already had a whole bunch of

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00:15:02,339 --> 00:15:07,560
existing libraries in robot Pi that were

288
00:15:05,880 --> 00:15:13,220
all camel case

289
00:15:07,560 --> 00:15:17,579
uh but this also lets students uh

290
00:15:13,220 --> 00:15:21,420
easily copy stuff from java code because

291
00:15:17,579 --> 00:15:25,500
there's a pretty healthy uh culture of

292
00:15:21,420 --> 00:15:26,760
sharing code uh within FRC

293
00:15:25,500 --> 00:15:29,519
um

294
00:15:26,760 --> 00:15:31,740
I think you I don't think I need to show

295
00:15:29,519 --> 00:15:33,480
any more code for for this hopefully you

296
00:15:31,740 --> 00:15:34,860
get the idea now

297
00:15:33,480 --> 00:15:37,680
um

298
00:15:34,860 --> 00:15:40,680
so that takes us to what we have today

299
00:15:37,680 --> 00:15:42,480
which is this sort of generalized build

300
00:15:40,680 --> 00:15:46,500
system for

301
00:15:42,480 --> 00:15:50,120
for generating these uh python these

302
00:15:46,500 --> 00:15:50,120
these C plus plus bindings

303
00:15:50,639 --> 00:15:57,899
so robot Pi build is a

304
00:15:55,139 --> 00:16:01,560
fairly opinionated build system for a

305
00:15:57,899 --> 00:16:04,079
python package so you use it to clear it

306
00:16:01,560 --> 00:16:04,740
in your Pi Project tunnel

307
00:16:04,079 --> 00:16:07,880
um

308
00:16:04,740 --> 00:16:11,220
reads reads your C plus plus headers

309
00:16:07,880 --> 00:16:12,240
generates some Pi by 11 code in the

310
00:16:11,220 --> 00:16:16,500
background

311
00:16:12,240 --> 00:16:19,260
and it will also package up your shared

312
00:16:16,500 --> 00:16:21,839
libraries or dlls in Windows parlance

313
00:16:19,260 --> 00:16:24,600
together with your python package when

314
00:16:21,839 --> 00:16:29,220
you upload it to IPI

315
00:16:24,600 --> 00:16:33,120
uh we use C types to load it at runtime

316
00:16:29,220 --> 00:16:36,480
so it's it works cross-platform but

317
00:16:33,120 --> 00:16:39,959
a consequence of us packaging them

318
00:16:36,480 --> 00:16:42,720
together is this is that we explicitly

319
00:16:39,959 --> 00:16:45,360
don't support binding to system

320
00:16:42,720 --> 00:16:47,279
libraries so if you need to use

321
00:16:45,360 --> 00:16:48,959
libraries that you have installed in

322
00:16:47,279 --> 00:16:53,120
your system you

323
00:16:48,959 --> 00:16:55,199
might be better to use Swig or shavokin

324
00:16:53,120 --> 00:16:59,459
or right

325
00:16:55,199 --> 00:17:00,300
Pi by an 11 code yourself I guess sorry

326
00:16:59,459 --> 00:17:02,600
um

327
00:17:00,300 --> 00:17:05,040
but yeah so so

328
00:17:02,600 --> 00:17:08,100
we end up with

329
00:17:05,040 --> 00:17:13,199
these data files that

330
00:17:08,100 --> 00:17:16,439
uh describe what headers to look at in

331
00:17:13,199 --> 00:17:22,860
this library that you're building

332
00:17:16,439 --> 00:17:25,980
um for what names you expect so both

333
00:17:22,860 --> 00:17:29,520
functions classes in arms things like

334
00:17:25,980 --> 00:17:33,059
that and also any particular special

335
00:17:29,520 --> 00:17:35,039
handling that you might need of

336
00:17:33,059 --> 00:17:38,660
so

337
00:17:35,039 --> 00:17:41,480
give you an overview of

338
00:17:38,660 --> 00:17:45,419
what our dependency graph looks like

339
00:17:41,480 --> 00:17:49,380
this is just the dependency graph for

340
00:17:45,419 --> 00:17:51,600
the same Library as our previous example

341
00:17:49,380 --> 00:17:54,179
just now

342
00:17:51,600 --> 00:17:57,980
um you might notice there's

343
00:17:54,179 --> 00:17:57,980
there's a whole bunch of different

344
00:17:58,380 --> 00:18:06,539
yeah we've got diamond dependencies and

345
00:18:02,280 --> 00:18:10,039
and there's also subclassing of

346
00:18:06,539 --> 00:18:12,799
of classes from each of these different

347
00:18:10,039 --> 00:18:17,340
uh libraries as well

348
00:18:12,799 --> 00:18:20,280
so this is where the pi bind 11 support

349
00:18:17,340 --> 00:18:21,600
for cross module class usage comes in

350
00:18:20,280 --> 00:18:22,919
because

351
00:18:21,600 --> 00:18:25,200
we've got

352
00:18:22,919 --> 00:18:28,140
there's been a library that has to be

353
00:18:25,200 --> 00:18:32,039
able to subclass a

354
00:18:28,140 --> 00:18:35,700
an interface that that's uh on one of

355
00:18:32,039 --> 00:18:39,360
our other libraries provides

356
00:18:35,700 --> 00:18:45,539
so this is what the pi project.tamil

357
00:18:39,360 --> 00:18:49,020
looks like so at the top uh we say that

358
00:18:45,539 --> 00:18:51,120
we want to to download

359
00:18:49,020 --> 00:18:56,220
uh

360
00:18:51,120 --> 00:18:59,760
uh our vendor Library uh and there's and

361
00:18:56,220 --> 00:19:02,280
yeah in FRC we've set up this uh

362
00:18:59,760 --> 00:19:06,600
standard convention uh that's

363
00:19:02,280 --> 00:19:09,720
maven-based uh for where to find

364
00:19:06,600 --> 00:19:13,080
uh find libraries

365
00:19:09,720 --> 00:19:18,240
and then we and then we start talking

366
00:19:13,080 --> 00:19:21,080
about our actual C our actual Pi bind 11

367
00:19:18,240 --> 00:19:21,080
wrapper

368
00:19:21,539 --> 00:19:26,720
um and you can see there we have this

369
00:19:24,299 --> 00:19:30,840
depends list

370
00:19:26,720 --> 00:19:36,059
s uh other packages that we've built

371
00:19:30,840 --> 00:19:40,559
using robot Pi build and this lets us

372
00:19:36,059 --> 00:19:42,179
actually link bitten to those other

373
00:19:40,559 --> 00:19:46,080
packages

374
00:19:42,179 --> 00:19:47,280
and then at the bottom uh we have a list

375
00:19:46,080 --> 00:19:51,059
of

376
00:19:47,280 --> 00:19:54,120
of headers that we want to look at this

377
00:19:51,059 --> 00:19:57,660
is just an excerpt so uh we're just

378
00:19:54,120 --> 00:20:00,020
going to be focusing on on this example

379
00:19:57,660 --> 00:20:00,020
here

380
00:20:00,720 --> 00:20:05,160
this is the same class from the previous

381
00:20:02,820 --> 00:20:07,280
example as well

382
00:20:05,160 --> 00:20:07,280
um

383
00:20:07,940 --> 00:20:15,320
so there is a little bit of new things

384
00:20:11,580 --> 00:20:19,860
in here where we have this keep alive

385
00:20:15,320 --> 00:20:23,400
thing so what this does is it's part of

386
00:20:19,860 --> 00:20:25,500
hiveine 11 and it lets you bind the

387
00:20:23,400 --> 00:20:28,620
lifetime of

388
00:20:25,500 --> 00:20:30,000
of one object to another

389
00:20:28,620 --> 00:20:32,940
so

390
00:20:30,000 --> 00:20:37,620
in this case so so here we have

391
00:20:32,940 --> 00:20:41,280
zero which is our return value and one

392
00:20:37,620 --> 00:20:45,059
which is self so this is saying that

393
00:20:41,280 --> 00:20:49,980
this PID controller thing that's

394
00:20:45,059 --> 00:20:53,580
returned by this method make sure that

395
00:20:49,980 --> 00:20:56,280
it doesn't outlive this

396
00:20:53,580 --> 00:21:00,059
can Spark Max

397
00:20:56,280 --> 00:21:01,760
so why else do you still have this PID

398
00:21:00,059 --> 00:21:06,200
controller object

399
00:21:01,760 --> 00:21:09,059
the cansbach max object would not be

400
00:21:06,200 --> 00:21:11,940
garbage collected

401
00:21:09,059 --> 00:21:16,080
and then at the bottom here we have a

402
00:21:11,940 --> 00:21:17,760
bit of inline code so this lets you uh

403
00:21:16,080 --> 00:21:22,020
shove

404
00:21:17,760 --> 00:21:25,200
some C plus plus code into the pi Vine

405
00:21:22,020 --> 00:21:27,900
11 module that's eventually generated

406
00:21:25,200 --> 00:21:31,799
and this allows us for infinite

407
00:21:27,900 --> 00:21:34,679
customization so here we actually add a

408
00:21:31,799 --> 00:21:39,120
method to the python class that doesn't

409
00:21:34,679 --> 00:21:39,780
exist on the C plus class

410
00:21:39,120 --> 00:21:42,080
um

411
00:21:39,780 --> 00:21:45,059
specifically here where

412
00:21:42,080 --> 00:21:49,559
adding a Dunder wrapper method

413
00:21:45,059 --> 00:21:52,380
just so that our users which are high

414
00:21:49,559 --> 00:21:54,780
school students can more easily debug

415
00:21:52,380 --> 00:21:57,659
their robot code right they don't care

416
00:21:54,780 --> 00:22:00,740
about the memory address which is what

417
00:21:57,659 --> 00:22:00,740
the default wrapper is

418
00:22:01,980 --> 00:22:07,860
there are other

419
00:22:04,500 --> 00:22:09,299
Pi bind 11 Auto generators out there

420
00:22:07,860 --> 00:22:11,940
um

421
00:22:09,299 --> 00:22:14,400
some of them are listed from the pi by

422
00:22:11,940 --> 00:22:17,940
11 documentation which I have also

423
00:22:14,400 --> 00:22:20,820
listed here I haven't had an opportunity

424
00:22:17,940 --> 00:22:25,440
to try them out but

425
00:22:20,820 --> 00:22:28,320
they do actually use clang and actual C

426
00:22:25,440 --> 00:22:29,880
plus plus compiler rather than a C plus

427
00:22:28,320 --> 00:22:31,919
plus parser that's been written in

428
00:22:29,880 --> 00:22:36,000
Python uh

429
00:22:31,919 --> 00:22:37,020
which does solve a lot of the edge cases

430
00:22:36,000 --> 00:22:40,440
in

431
00:22:37,020 --> 00:22:43,559
having to pass C plus plus because

432
00:22:40,440 --> 00:22:46,380
there because

433
00:22:43,559 --> 00:22:49,760
it's it's a lot harder to parse C plus

434
00:22:46,380 --> 00:22:49,760
plus than you might think

435
00:22:51,299 --> 00:22:53,720
okay

436
00:22:54,539 --> 00:23:02,100
so you might be wondering then how do we

437
00:22:58,320 --> 00:23:06,000
ship all these libraries to our users

438
00:23:02,100 --> 00:23:09,900
right we basically just want them to be

439
00:23:06,000 --> 00:23:12,179
able to pip install robot pi and things

440
00:23:09,900 --> 00:23:16,380
work

441
00:23:12,179 --> 00:23:18,320
so what we do is we build a bunch of

442
00:23:16,380 --> 00:23:22,020
wheels in CI

443
00:23:18,320 --> 00:23:24,780
we have a lot of repos so we created

444
00:23:22,020 --> 00:23:27,919
this reusable workflow which is a GitHub

445
00:23:24,780 --> 00:23:30,559
actions feature where you can say hey

446
00:23:27,919 --> 00:23:34,200
this this CI pipeline

447
00:23:30,559 --> 00:23:38,299
should just run this CI pipeline that's

448
00:23:34,200 --> 00:23:38,299
that's defined in this other repo

449
00:23:38,760 --> 00:23:45,299
you know we build for the three

450
00:23:42,120 --> 00:23:47,700
big operating systems for all the

451
00:23:45,299 --> 00:23:50,520
currently supported C python versions

452
00:23:47,700 --> 00:23:53,460
so

453
00:23:50,520 --> 00:23:59,400
that ends up being 15 wheels that we

454
00:23:53,460 --> 00:24:02,700
upload to Pipi and we deploy these

455
00:23:59,400 --> 00:24:05,760
whenever we push a git tag so that

456
00:24:02,700 --> 00:24:07,380
that's part of the CI pipeline as well

457
00:24:05,760 --> 00:24:09,559
is that

458
00:24:07,380 --> 00:24:13,640
it checks whether

459
00:24:09,559 --> 00:24:13,640
we've just pushed the git tag

460
00:24:13,919 --> 00:24:19,679
and we also build a bunch of arm Wheels

461
00:24:17,820 --> 00:24:22,100
as well and we have a private repo for

462
00:24:19,679 --> 00:24:28,080
those this is because

463
00:24:22,100 --> 00:24:29,700
the uh the main controller that's used

464
00:24:28,080 --> 00:24:34,860
in

465
00:24:29,700 --> 00:24:37,200
FRC is a bit of an unusual Linux

466
00:24:34,860 --> 00:24:38,760
um platform

467
00:24:37,200 --> 00:24:42,179
but

468
00:24:38,760 --> 00:24:45,900
we also but yeah we do also Target

469
00:24:42,179 --> 00:24:49,620
raspbian but because arm is so diverse

470
00:24:45,900 --> 00:24:51,720
right like what uh like as general said

471
00:24:49,620 --> 00:24:53,520
like what arm are you are you talking

472
00:24:51,720 --> 00:24:57,480
about right

473
00:24:53,520 --> 00:25:01,320
so we decide that we don't want to deal

474
00:24:57,480 --> 00:25:04,260
with that uh when uploading to Pi Pi and

475
00:25:01,320 --> 00:25:08,580
users have to explicitly opt in to

476
00:25:04,260 --> 00:25:09,840
actually using our our Wheels

477
00:25:08,580 --> 00:25:12,900
now

478
00:25:09,840 --> 00:25:16,740
our Wheels do technically fail audit

479
00:25:12,900 --> 00:25:18,840
wheel which is the the many Linux

480
00:25:16,740 --> 00:25:19,799
auditor

481
00:25:18,840 --> 00:25:23,779
um

482
00:25:19,799 --> 00:25:26,360
and this is because of our cross package

483
00:25:23,779 --> 00:25:30,779
Library dependencies

484
00:25:26,360 --> 00:25:33,960
they do otherwise satisfy many Linux

485
00:25:30,779 --> 00:25:38,159
as last time I checked

486
00:25:33,960 --> 00:25:41,700
so and we just end up renaming the

487
00:25:38,159 --> 00:25:44,580
wheels NCI just before we upload to Pi

488
00:25:41,700 --> 00:25:48,900
Pi and

489
00:25:44,580 --> 00:25:52,940
we haven't had complaints so

490
00:25:48,900 --> 00:25:52,940
I I'm pretty sure it works

491
00:25:53,100 --> 00:25:56,820
that's all I have

492
00:25:54,960 --> 00:25:59,820
um

493
00:25:56,820 --> 00:26:02,039
if you want to check out check this out

494
00:25:59,820 --> 00:26:06,059
there's a link to the tower repo and our

495
00:26:02,039 --> 00:26:08,159
docs we also have a matrix Channel

496
00:26:06,059 --> 00:26:10,559
and

497
00:26:08,159 --> 00:26:12,900
yeah

498
00:26:10,559 --> 00:26:16,580
thank you

499
00:26:12,900 --> 00:26:16,580
thank you very much David

500
00:26:17,340 --> 00:26:20,840
we've got a little bit of time for

501
00:26:18,600 --> 00:26:20,840
questions

502
00:26:22,260 --> 00:26:27,539
I'm curious about how

503
00:26:24,419 --> 00:26:30,059
um how many other

504
00:26:27,539 --> 00:26:31,080
is it using other robot platforms or on

505
00:26:30,059 --> 00:26:35,100
other

506
00:26:31,080 --> 00:26:40,100
um uh C plus plus projects yet

507
00:26:35,100 --> 00:26:42,299
so I do believe that one of our

508
00:26:40,100 --> 00:26:47,279
co-maintainers the main maintainer

509
00:26:42,299 --> 00:26:49,740
actually uh has used it at work

510
00:26:47,279 --> 00:26:52,980
um I'm not entirely sure on the details

511
00:26:49,740 --> 00:26:55,799
because work stuff I guess but yeah yeah

512
00:26:52,980 --> 00:26:58,500
cool there's a question at the front uh

513
00:26:55,799 --> 00:26:59,880
question I had was why you went down the

514
00:26:58,500 --> 00:27:03,539
route of Auto

515
00:26:59,880 --> 00:27:05,700
generating the pi bind uh code rather

516
00:27:03,539 --> 00:27:08,159
than handwriting it that's a good

517
00:27:05,700 --> 00:27:13,020
question yeah so

518
00:27:08,159 --> 00:27:17,340
the libraries that we had to to uh

519
00:27:13,020 --> 00:27:18,840
package are actually very large like

520
00:27:17,340 --> 00:27:22,260
um

521
00:27:18,840 --> 00:27:25,260
like we like in one of our libraries we

522
00:27:22,260 --> 00:27:28,140
have like uh

523
00:27:25,260 --> 00:27:30,419
I want to say like at least 50 different

524
00:27:28,140 --> 00:27:31,260
classes

525
00:27:30,419 --> 00:27:35,279
um

526
00:27:31,260 --> 00:27:37,020
there's also the one of our

527
00:27:35,279 --> 00:27:40,740
our packages is

528
00:27:37,020 --> 00:27:43,020
um some maths very maths heavy

529
00:27:40,740 --> 00:27:44,820
um and so there's a bunch of classes in

530
00:27:43,020 --> 00:27:46,679
there and

531
00:27:44,820 --> 00:27:48,419
we want to use C plus for performance

532
00:27:46,679 --> 00:27:51,559
reasons there

533
00:27:48,419 --> 00:27:51,559
um but then

534
00:27:52,080 --> 00:27:58,760
actually yeah yeah that's a lot happened

535
00:27:54,960 --> 00:27:58,760
cool any other questions

536
00:28:01,320 --> 00:28:05,820
so I was just curious if you'd looked at

537
00:28:02,940 --> 00:28:07,860
using uh CI build will to solve some of

538
00:28:05,820 --> 00:28:09,299
those like Auto wheel compatibility

539
00:28:07,860 --> 00:28:11,220
issues

540
00:28:09,299 --> 00:28:12,720
it's a good question

541
00:28:11,220 --> 00:28:15,240
um

542
00:28:12,720 --> 00:28:17,340
I did have a brief look at it

543
00:28:15,240 --> 00:28:23,480
um but

544
00:28:17,340 --> 00:28:25,679
I'm not sure that CI build will support

545
00:28:23,480 --> 00:28:29,100
uh the

546
00:28:25,679 --> 00:28:31,080
uh Ubuntu versions that we have to

547
00:28:29,100 --> 00:28:32,520
actually Target

548
00:28:31,080 --> 00:28:33,960
um

549
00:28:32,520 --> 00:28:36,000
this is a good question I'll have to

550
00:28:33,960 --> 00:28:37,500
double check on that

551
00:28:36,000 --> 00:28:39,840
cool

552
00:28:37,500 --> 00:28:42,140
anyone else I'll just walk yep time for

553
00:28:39,840 --> 00:28:42,140
one more

554
00:28:45,000 --> 00:28:48,240
hello

555
00:28:45,960 --> 00:28:51,240
um just wondering if your approach works

556
00:28:48,240 --> 00:28:54,179
with very heavily templated libraries or

557
00:28:51,240 --> 00:28:55,679
header only libraries yes excellent

558
00:28:54,179 --> 00:28:59,640
question yes

559
00:28:55,679 --> 00:29:02,520
um so uh a few of our libraries are

560
00:28:59,640 --> 00:29:04,500
actually pretty template heavy and so we

561
00:29:02,520 --> 00:29:07,200
do have explicit support for that in

562
00:29:04,500 --> 00:29:10,440
robot pie build as well you do have to

563
00:29:07,200 --> 00:29:15,360
manually list out all the the template

564
00:29:10,440 --> 00:29:18,120
instantiations that you want but yes

565
00:29:15,360 --> 00:29:18,870
very cool and please join me in thanking

566
00:29:18,120 --> 00:29:20,480
David once again

567
00:29:18,870 --> 00:29:22,430
[Applause]

568
00:29:20,480 --> 00:29:25,359
thank you so much

569
00:29:22,430 --> 00:29:25,359
[Applause]