To: J3                                                     J3/23-162
From: T. Clune
Subject: Intrinsic procedures as template arguments
Date: 2023-June-08

#Reference:

Fortran has a number of intrinsic procedures that do not have specific
names, and therefore cannot be used as actual arguments to procedures.
Now though, the proposed approach to Fortran features for generic
programming allow a generic procedure name to be used as an actual
argument to a template deferred procedure dummy argument.  This begs
the question of whether _intrinsic_ procedures with generic names can
be used in this new context.

This paper proposes to amend the standard to allow certain intrinsic
procedures to be used as template arguments where
appropriate/sensible.  The poster children for this capability are the
math functions: SQRT(), SIN(), LOG(), ..., etc.

Possibly no change is needed for this (beyond the new generic
programming features themselves), as the standard already describes
some intrinsics in terms of having a generic name.  Nonetheless, since
many intrinsics are "magic", the situation is not entirely clear to
me.  At a minimum, I think a clarifying remark in chapter 16 would be
appropriate.