Perform assignment only if right side is not nil

Question

Is there a possibility to only perform an assignment (e.g. to a non-optional property) if the right hand side is not nil? I am looking for a one-line form for:

Answer 1

There are various ways that aren't too unwieldy

Using ?? :

object.nonOptionalProperty = funcThatReturnsOptional() ?? object.nonOptionalProperty 

Using a function :

func setNotNil(inout variable:T, _ value:T?)
{ if value != nil { variable = value! } }

setNotNil(&object.nonOptionalProperty, funcThatReturnsOptional())

Using an operator :

infix operator <-?? { associativity right precedence 90 assignment }
func <-??(inout variable:T, value:T?)
{ if value != nil { variable = value! } }

object.nonOptionalProperty <-?? funcThatReturnsOptional() 

Using an extension :

extension Equatable
{ mutating func setNotNil(value:Self?) { if value != nil { self = value! } } }

object.nonOptionalProperty.setNotNil(funcThatReturnsOptional())