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calling a method of a super class during initialization
f#

Hello,

How can I call a method of a super class during initialization of
a subclass (v.1.9.6.2)?

E.g.

type Base =
val i: int
new (x) = { i = x }
member this.dup () = this.i * 2

type SubBase =
inherit Base
val j: int
new () = { inherit Base(0); j = 0 }
new (x) as this = { inherit Base(x); j = this.dup () }

let b = new SubBase (3) // Null exception

I thought this worked in a previous version, but I might be wrong...

.

AFAIK, "this" won't be valid until the constructor completes. So instead of j = this.dup() you want j = base.dup(). That works in 1.9.6.16 anyways.

By on 9/8/2009 5:35 AM ()

Hmmm,

So I can call a method of a super class via base
but cannot access a field of a super class via base?

// This works.
type SubBase =
inherit Base
val j: int
new (x) as this = { inherit Base(x); j = base.dup () };;

// This does compile.
type SubBase2 =
inherit Base
val j: int
new (x) as this = { inherit Base(x); j = base.i };;

By on 9/8/2009 5:55 AM ()

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