(j3.2006) IMPLICIT NONE in BLOCK

[Van Snyder]

On Fri, 2018-02-23 at 00:03 -0800, Robert Corbett wrote:
> If a user wants IMPLICIT NONE to be in effect within a BLOCK
> construct, he or she should put an IMPLICIT NONE statement in a
> non-BLOCK scoping unit containing the BLOCK construct.  Because it is
> good practice to always use IMPLICIT NONE, putting IMPLICIT NONE in
> one or more of the containing scoping units should not be too great a
> burden.

The situation that Vipul Parekh discussed, and that I repeated, involved
maintenance of a large antique legacy code.  It might not be
economically feasible to add IMPLICIT NONE at procedure scope and then
add explicit declarations for everything.  The primary reason for using
BLOCK constructs in this situation is to minimize labor cost.  Indeed,
the only reason for the existence of high-level programming languages is
to minimize labor cost.

So, to get back to the original question, rather than deflect discussion
of it toward new codes only, would it be feasible to allow IMPLICIT
NONE, and no other kind of IMPLICIT for the reasons we all understand,
in BLOCK constructs?  I don't see how it could affect existing codes.
The question boils down to the effect on processors and the standard.