The type signature notation used in this document is described below:1 :: "is a member of". e :: t can be read as: "the expression e is a member of type t". true :: Boolean - "true is a member of type Boolean". 42 :: Integer, Number - "42 is a member of the Integer and Number types". New types can be created via type constructors. Type constructors can take zero or more type arguments. Array is a
 
     
       
       
       
       
       
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