lispdoc - results for subtypep

(subtypep type1 type2 &optional environment)
Function: Return two values indicating the relationship between type1 and type2. If values are T and T, type1 definitely is a subtype of type2. If values are NIL and T, type1 definitely is not a subtype of type2. If values are NIL and NIL, it couldn't be determined.
 Mentioned in:
CLtL2 - 17.1. Array Creation
CLtL2 - 17.3. Array Information
CLtL2 - 4.5. Type Specifiers That Specialize
CLtL2 - 4.9. Determining the Type of an Object
CLtL2 - 6.2.1. General Type Predicates
HyperSpec - Function SUBTYPEP