Intel Fortran Language Reference - NCI National Facility

8 Intel Fortran Language Reference
The actual argument and corresponding dummy procedure must both be subroutines or both be
functions.
If the interface of the dummy procedure is explicit, the type and kind parameters, and rank of the
associated actual procedure must be the same as that of the dummy procedure.
If the interface of the dummy procedure is implicit and the procedure is referenced as a subroutine,
the actual argument must be a subroutine or a dummy procedure.
If the interface of the dummy procedure is implicit and the procedure is referenced as a function or
is explicitly typed, the actual argument must be a function or a dummy procedure.
Dummy procedures can be declared optional, but they must not be declared with an intent.
The following is an example of a procedure used as an argument:
REAL FUNCTION LGFUNC(BAR)
INTERFACE
REAL FUNCTION BAR(Y)
REAL, INTENT(IN) :: Y
END
END INTERFACE
...
LGFUNC = BAR(2.0)
...
END FUNCTION LGFUNC
See Also
“Argument Association”
References to Generic Procedures
Generic procedures are procedures with different specific names that can be accessed under one
generic (common) name. In FORTRAN 77, generic procedures were limited to intrinsic
procedures. In Fortran 90, you can use generic interface blocks to specify generic properties for
intrinsic and user-defined procedures.
If you refer to a procedure by using its generic name, the selection of the specific routine is based
on the number of arguments and the type and kind parameters, and rank of each argument.
All procedures given the same generic name must be subroutines, or all must be functions. Any
two must differ enough so that any invocation of the procedure is unambiguous.
The following sections describe references to generic intrinsic functions and show an example of
using intrinsic function names.
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