45 lines
1.4 KiB
Forth
45 lines
1.4 KiB
Forth
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module Inheritance
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//The following code example illustrates the declaration of
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// a new virtual method function1 in a base class
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// and how to override it in a derived class.
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type MyClassBase1() =
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let mutable z = 0
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abstract member function1 : int -> int
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default u.function1(a : int) = z <- z + a; z
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type MyClassDerived1() =
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inherit MyClassBase1()
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override u.function1(a: int) = a + 1
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//The following code shows a base class and a derived class,
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// where the derived class calls the base class constructor in the inherit clause:+
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type MyClassBase2(x: int) =
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let mutable z = x * x
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do for i in 1..z do printf "%d " i
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type MyClassDerived2(y: int) =
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inherit MyClassBase2(y * 2)
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do for i in 1..y do printf "%d " i
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//In the case of multiple constructors, the following code can be used.
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// The first line of the derived class constructors is the inherit clause,
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// and the fields appear as explicit fields that are declared with the val keyword.
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// For more information, see Explicit Fields: The val Keyword.
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type BaseClass =
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val string1 : string
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new (str) = { string1 = str }
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new () = { string1 = "" }
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type DerivedClass =
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inherit BaseClass
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val string2 : string
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new (str1, str2) = { inherit BaseClass(str1); string2 = str2 }
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new (str2) = { inherit BaseClass(); string2 = str2 }
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let obj1 = DerivedClass("A", "B")
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let obj2 = DerivedClass("A")
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