my custom collection example implements ienumerable(of long) , idictionary(of string, long).
when enumerate through collection for each, values of type keyvaluepair(of string, long), want values of type long.
the 3 getenumerator's only differ in return type. not overloading.
module main sub main() dim examples new example each e in examples ' e of type keyvaluepair(of string, long) ' want e of type long next end sub end module public class example implements ienumerable(of long), idictionary(of string, long) private property thekeyedcollection keyedcollection(of string, long) public function getenumerator() ienumerator(of keyvaluepair(of string, long)) implements ienumerable(of keyvaluepair(of string, long)).getenumerator return thekeyedcollection.getenumerator() end function public function getenumerator1() ienumerator(of long) implements ienumerable(of long).getenumerator return thekeyedcollection.getenumerator() end function public function getenumerator2() ienumerator implements ienumerable.getenumerator return thekeyedcollection.getenumerator() end function '>>>>>>>>>>>>>>>>>>>>>>>>>>>> ignore these other unnecessary functions <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< private sub add(item keyvaluepair(of string, long)) implements icollection(of keyvaluepair(of string, long)).add end sub private sub clear() implements icollection(of keyvaluepair(of string, long)).clear end sub private function contains(item keyvaluepair(of string, long)) boolean implements icollection(of keyvaluepair(of string, long)).contains throw new exception end function private sub copyto(array() keyvaluepair(of string, long), arrayindex integer) implements icollection(of keyvaluepair(of string, long)).copyto end sub private readonly property count integer implements icollection(of keyvaluepair(of string, long)).count throw new exception end end property private readonly property isreadonly boolean implements icollection(of keyvaluepair(of string, long)).isreadonly throw new exception end end property private function remove(item keyvaluepair(of string, long)) boolean implements icollection(of keyvaluepair(of string, long)).remove throw new exception end function private sub add1(key string, value long) implements idictionary(of string, long).add end sub private function containskey(key string) boolean implements idictionary(of string, long).containskey end function '>>>>>>>>>>>>>>>>>>>>>>>>>>>> ignore these other unnecessary functions <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< private property item(key string) long implements idictionary(of string, long).item throw new exception end set(value long) end set end property private readonly property keys icollection(of string) implements idictionary(of string, long).keys throw new exception end end property private function remove1(key string) boolean implements idictionary(of string, long).remove throw new exception end function private function trygetvalue(key string, byref value long) boolean implements idictionary(of string, long).trygetvalue throw new exception end function private readonly property values icollection(of long) implements idictionary(of string, long).values throw new exception end end property '>>>>>>>>>>>>>>>>>>>>>>>>>>>> ignore these other unnecessary functions <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< end class i tried setting getenumerator() , getenumerator2() private, produced error: 'for each' on type 'example.example' ambiguous because type implements multiple instantiations of 'system.collections.generic.ienumerable(of long)'.
how pick getenumerator() for each uses?
change name of function want default enumerator getenumerator(). not getenumerator1().
if don't plan use other 2 versions of getenumerator, can set them private, still have there satisfy given interface.
if want use 1 of getenumerator()s not default, i.e. getenumerator1(), need force for each infer this:
for each e in directcast(example, ienumerable(of string)) ' e of type string next 
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