Components |Functions |June Expermental |Breaks Code Libs created using components

[PeterCBell_au]

Creating Canvas Powerapps.

I have a number of components with properties and parameters that interact (eg. date functions specific to my industry) .

I used component output properties to provide functions and those properties used other properties (passing parameters) within the same component. ie. FuncA with parameters a and b may call Func1 and Func2.  (eg. property FuncA returns Self.Func1(a,b) * Self.Func2(b) + Self.Func3(a) etc.)

The new restriction means that a data output doesnt have parameters and may only reference the controls on the component (ie. not suitable for general purpose calculations)  --> Any of my outputs (that were emulating an output function) that referenced other properties in the same component are now broken.

The output functions may only perform calculations using their own parameters and cannot call other functions in the component.

So... How do I build a base library of functions that can be called by other functions?

Previous documentation suggested 'user defined functions' defined in the app formulas section would be coming, and would be of the form... 

                      udfTest(par1:Number , par2:Number, par3:Number):Number=  (par1*par2)/par3

I was hoping that when this was released I could move code out of components and create a number of UDF procedures that were callable from within the app (and by components with app scope) and could call each other.

But trying to enter a udf (using the syntax above) fails. Have UDF's been implemented but using some other syntax??

Related to the above, I dont follow the documentation regarding input functions for components- how do I define a function in the app that has parameters that the input function can make a callback to (ie. a udf as mentioned above)? 

from... "learn.microsoft.com/en-au/power-apps/maker/canvas-apps/component-properties""

"The app could define the function expression to return $"{firstname} {lastname}" or it could choose to define an expression for $"{lastname}, {firstname}". The component can just call the function the app maker has provided, and use the returned string."

[PeterCBell_au]

Thanks Joris. Code only components seemed to be working fine. The real issue was the kludginess of using the interface. More advanced users being able to download/upload plain text would ease my tasks (my organisation keeps me in powerapps studio) which i guess i was hoping udf's were going to bring to the table. 

[JorisdG]

The first wave of UDFs they will pretty much be like named formulas and how you define those. We're brainstorming on user experience after that, but that's what you should expect in the short-term.

[PeterCBell_au]

Hi Joris

 Have you had any luck undoing the lock that was placed on component functions allowing parameters?

 I have a large project with a lot of base functions (which were working perfectly fine) awaiting restoration.

 If the functionality isnt going to be restored and UDF's arent being released until >= Sep 2023 then I will have to invest many man hours to work around the errors- It would be helpful for me to know one way or the other.

[JorisdG]

Functions calling functions will be rolling out in the next few weeks with regular schedule. Enabling data flow so we can allow state to be used inside functions is something we're reviewing. Work was done for UDFs to support data flow properly, and we're hoping to uptake this for the components already (i.e. before UDFs are released). I don't have a timeline yet, but I will keep this thread updated as we are actively looking into it.

[PeterCBell_au]

Thanks Joris- I look forward to the fix being implemented and (hopefully) UDF's

[qwertyuiop]

Hi Joris. I wanted to see if the UDF functionality will be released soon? I was looking and Wave 2 and saw it wasnt on the roadmap anymore. Is it possible to sign on as a tester? I was waiting for this functionality to help develop the next generation apps for my org.

[PeterCBell_au]

Hi Joris,

 In the leadup to the release, might I make a few observations.

 The app formulas repository can contain quite a few formulas already, making navigation difficult and also spotting the little red squiggle difficult when there are errors (plus an error in one formula breaks dependent formulas). Transferring code from component libraries will exacerbate the issue.

 Perhaps a tree to the left listing the left side of each formula (formula name) with red text if a formula is in error and click a formula name navigates to the correct line in the editor? Also, if the app formulas editor allowed sections (section start indicated by a line beginning with a # and what follows is the section name, until end of code or new section start delimiter) would allow the formula names tree to have parent nodes as section names and children as formula names.

Occasionally, the editor can have trouble with errors and deciding when to reset its error parsing and labels 'clean' code as in error- sections would make it simpler for the parser to 'reset' after detecting errors.

Within the concept of reusable blocks; it would be great if custom components could be used within other components and that the base class for a component inherited a container.

[JorisdG]

@qwertyuiop UDFs are still actively being worked on. We hit a snag with the release wave notes but rest assured it's still in the works, just pushed out a little bit. Still expecting it in the next few months.

@PeterCBell_au some improvements are rolling out for performance of editing named formulas. We have several designs and plans for a better UX (based on the variables and collections pane) but it's not prioritized at this moment. I realize with UDFs going into the same property this will get larger and larger, but that will hopefully give us the momentum to prioritize the UX options.

[Ramspevi]

Hello @JorisdG 
I have to say that I am a bit confused right now. 

Talk about implementing UDFs started last year, with a Pupblic Preview release in February then it was moved to September. Since then dead silence. Despite removing UDFs from the release plan (https://releaseplans.microsoft.com/en-US/?app=Power+Apps&status=new), but that's not whats confusing me. It's that in the german version of release plan UDFs are in "Try Now" with a public preview date for September....


The whole release planner is out of sync between the different languages. I don't know if you could do something about it but you might know the person who can fix this. 

I and I guess many others do heavily rely on the release planner to plan updates and publications of our apps.

[JorisdG]

Yes, we started on UDFs last year in the summer (with an intern). You can follow our actual Power Fx language work on Github under https://github.com/Microsoft/Power-Fx - all our language work is done wide open. You'll find after the initial work was done by our intern, we picked up the work around April to finish it as a language feature. What you can't see there is the work then needed to uptake it in Power Apps (how to edit, where to store, how to incorporate it into the analysis engine, etc.). We were planning for September, which we actually finished but we ended up having to take a dependency on another new feature (new analysis engine) that won't be out for another several weeks, unfortunately. Pushing the feature to the next wave somehow removed it everywhere which I'm not sure how or why that happened. You will still get an experimental preview of UDFs before the end of the year.

As for the issue with German or other language release plans not updating, I'm not exactly sure who to talk to but I will bring it up with my management and hopefully they can pass on that feedback to get it fixed!