Source : Free On-Line Dictionary of Computing

CPL
     
        Combined Programming Language.  U Cambridge and U London.  A
        very complex language, syntactically based on ALGOL 60, with a
        pure functional subset.  Provides the ..where.. form of local
        definitions.  Strongly typed but has a "general" type enabling
        a weak form of polymorphism.  Functions may be defined as
        either normal or applicative order.  Typed array and
        polymorphic list structures.  List selection is through
        structure matching.  Partially implemented on the Titan (Atlas
        2) computer at Cambridge.  Led to the much simpler BCPL.  "The
        Main Features of CPL", D.W. Barron et al, Computer J
        6(2):134-143 (Jul 1963).