Query: Translate Math.PI

[bricelam]

See #24829 (comment)

[Marusyk]

I will try to prepare a PR for this

[smitpatel]

In the associated PR, we came to know that Math.PI is inlined as a constant value inside expression by C# compiler directly. This makes us never see Math.PI member expression in tree itself so this is not something we can interpret and translate. The constant value will always be sent to server as constant, as we receive it from C# compiler.

[bricelam]

Crazy idea: Replace Expression.Constant(Math.PI) with Expression.MakeMemberAccess(null, typeof(Math).GetField("PI")) in the preprocessor. Obviously, this would catch any constant that happens to equal .NET's approximation of PI, but is that really an issue?

If we do this, we should also do it for E and Tau.

[ajcvickers]

Note from triage: funcletization complicates this, and there seems to be very little value. Closing.

[roji]

Technically the complication is even before ParameterExtractingEV (funcletization) - as above since Math.PI is a constant, the incoming expression tree doesn't even contain it, only the inlined constant value. So I think there's really nothing we can do here, even in theory.