Difference between revisions of "New CAT call"

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==Detachable type==
 
==Detachable type==
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According to the new approach a detachable type can be attached to an object of "any" type.

Revision as of 13:48, 27 October 2006

Introduction

The ECMA standard introduces a new solution to the CAT call problem. Covariant redefinition of a formal argument is only possible to a detachable type:

class A
feature
   f (a: ANY) do end
end
class B1
inherit A redefine f end
feature
   f (a: STRING) do end   -- not valid
end
class B2
inherit A redefine f end
feature
   f (a: ?STRING) do end   -- valid
end

This wiki discusses some of concerns related to this solution.

Detachable type

According to the new approach a detachable type can be attached to an object of "any" type.