Mutability of struct cross languages

[Xyncgas]

If I made a struct in C#, with member to mutate it
Now in F# I create the struct and I call that member
The question is, in this scenario, is it mutable without me using mutable keyword, in F# standard, for one I feel conflicted

[realparadyne]

Yes it is.

[Xyncgas]

So you support the idea it can be mutated or you are saying it actually mutates the struct
Because it doesn't for me, it might be a bug or not it's weird

[realparadyne]

I'm saying I tested it out of interest, and the member function can mutate fields in the struct. The struct, its definition and code for members exist outside of F#, it would not be really possible for the F# compiler to analyse the IL of a library it is referencing to determine that what a member does internally is somehow not allowed. Then we would be in real trouble trying to use all of the .Net libraries!