Over-enthusiastic removal of parentheses

[SteveGilham]

Before

match i.Operand with
                            | :? (Instruction[]) -> true
                            | _ -> false

After

match i.Operand with
                            | :? Instruction [] -> true
                            | _ -> false

error FS0010: Unexpected symbol'[' in pattern matching. Expected '->' or other token.

[SteveGilham]

Also in cast expression

i.Operand :?> (Instruction [])

becoming

i.Operand :?> Instruction []

with the same compiler error.

[jindraivanek]

First case fixed by #317.

Wasn't able to reproduce second case, for example ([] :> obj) :?> int seq is valid code.

@SteveGilham, if you still see this as error, please post self-contained snippet for this case.