Should the syntax rules require or allow the multiple-specification of a subprogram the following variations are permitted:
Two specifications for one subprogram are conform if - irrespective of comments and the variations mentioned above - both specifications are made up of the same sequence of lexical elements and corresponding lexical elements have the same meaning. The specification of a impure function is never conform to that of a pure function
The specifications for the procedure p are not conform as they are not made up of the same sequence of lexical elements.
PROCEDURE p ( x, y : integer ); PROCEDURE p (x : integer ; y : integer); PROCEDURE p ( x, y : IN integer );