f# - call abstract function from a method's own implementation -


i have tried call abstract function method's own implementation.

[<abstractclass>] type callanabstract () =       let dosomethingelse () = printfn "done something.."      abstract dosomethingabstract: unit -> unit      member this.dosomething =         printfn "done something.."         dosomethingelse ()         dosomethingabstract ()

which results in error:

error fs0039: value or constructor 'dosomethingabstract' not defined

is calling abstract function method's own implementation illegal or problem lie somewhere else?

if being illegal case, here (see answer) @mark seemann explains composition on inheritance:

[<abstractclass>] type usecomposition (dosomethingelsedefinedlater) =       let dosomethingelse () = printfn "done something.."      member this.dosomething =         printfn "done something.."         dosomethingelse ()         dosomethingelsedefinedlater ()

what alternatives? i'd avoid passing function via constructor , i'd reuse code, having dosomething have "some implementation" until call abstract function.

you need use this reference:

this.dosomethingabstract()

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