[1] : The Free On-line Dictionary of Computing (27 SEP 03)

subtype
     
         if s is a subtype of t then an expression of
        type s may be used anywhere that one of type t can and an
        implicit type conversion will be applied to convert it to
        type t.
     
        in object oriented programming, this means that objects of
        type s must accept every message that one of type t would.
     
        1997-07-28
     
     
see also:
type implicit type conversion object oriented programming objects message 

Subtype >> S Words
Subtype, definition of term: Subtype
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