With only <T: Numeric> type, how to create an NSNumber?

Edit: solution to this question.

All the numeric types NSNumber support except Bool and CChar, exactly these I copy from all the init(value:)'s:

Double
Float
Int32
Int
Int64
Int16
UInt8
UInt32
UInt
UInt64
UInt16

this is my original question about casting an NSNumber to a <T: that-NSNumber-Support-Except-Bool-And-CChar>