fun(...) crashes in iOS for versions of Language-Ext later than 3.1.24

I have observed, that every version later than 3.1.24 causes a crash on iOS, when creating a function using fun(...).

I’ve created a simple project to illustrate this issue here: https://github.com/1iveowl/Language-Ext-Issue-Recreate.

Run the iOS project on a real device and press the button number 2, and you will get a crash from the line var testFunc = fun((int x) => Task.Delay(TimeSpan.FromSeconds(x)));.

In the project I use Language-Ext version 3.3.20. If I change the project to use Language-Ext version 3.1.24 then the crash will no longer occur.

Note: I’ve only seen the issue on a real iOS device. If I run the project in the simulator I do not see a crash.

Might be related to #632

[TysonMN]

So, I’ve stripped away all the partial parts of the Prelude class, trying to introduce all the static values one by one, in an effort to pinpoint when the crash happens, so that I can start creating a possible fix/workaround. This is obviously tedious work, as I have to build and run the iOS app on a device for every single try.

Don’t do this “one by one”. Cut your search space in half each time just like binary search.

Start with some set of static values such that the program crashes. Comment out half of them. Test. If the program crashes, then repeat with the set of static values still commented in. If the program did not crash, then repeat with the set of static values that were just commented out.

My guess is that you are merely searching in Prelude for some static value that extends from Record<>, which means that this issue is a special case of #632.

[1iveowl]

My mistake. The first paragraph have now been updated. I hope this clears the confusion?