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Mutually recursive generic types and Type Mismatch error
f#

F# Version 1.9.6.16. This may be the same issue as: [link:cs.hubfs.net]. Here is a smallest code that reproduces the problem. What am I doing wrong?

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type T1<'t> () = 
   member me.Something() = 0 (* FS0001 *)

and T2<'t> (t1:T1<'t>) =
   let y = t1.Something ()

Now, the two types must be mutually recursive for other reasons; this is only a dumbed down snippet to show the problem. The compilation error that I am receiving is:
error FS0001: Type mismatch. Expecting a T1<'t> but given a T1<'t0>. The type ''t' does not match the type ''t0'Non-generic types can be defined this way.
Why?

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I think possibly this is just a bug; you can work around it by specifying the full type signature (in this case, the return type ":int"):

member me.Something() : int = 0 (* ok *)

I expect in Beta2 this will 'just work'.

By on 7/25/2009 9:46 PM ()

you can work around it by specifying the full type signature

Huh! That worked. Thank you!

By on 7/25/2009 10:27 PM ()

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