J3/01-159

Date:    3 March 2001
To:      J3
From:    John Reid
Subject: Interpretation 25 (List-directed input: types of variables
         corresponding to repeated values)

Here is a draft answer for interp. 25. This was discussed at Oulu
without reaching a resolution. WG5 commented as follows (WG5/N1410)

   Section 10.8 [175:7-9] states: "The r*c form is equivalent to r
   successive appearances of the constant c, and the r* form is
   equivalent to r successive appearances of the null value."

   WG5/interp  was unable to agree on whether r*c implied r copies of
   the characters in c or r copies of the constant implied by c,
   possibly after the association of the first copy in the input record
   with its associated list item.  Both interpretations are possible
   from the text.  The answer to the question is accordingly no or
   yes.

I have prepared a draft answer based on the first alternative, because
I believe that this is what was intended and it is what most compilers
do.

..................................................

NUMBER: 000025
TITLE: List-directed input: types of variables corresponding to repeated values
KEYWORDS:
DEFECT TYPE: Erratum
STATUS: J3 consideration in progress

QUESTION:

When a repeat count is used in list-directed input, must all the variables into
which the repeated value is read have the same type?  I see no reason in the
standard to assume that restriction, but at least one Fortran 90 implementation
assumes it.

ANSWER:

No, the variables are not required to be of the same type, but it is
intended that the whole of <c> be acceptable for each item corresponding
to the input form <r*c>. For example, the input
   2*(1.0, 0.0)
does not conform to the standard when any of the list items is of type
character.

An edit is provided to clarify the situation.

EDIT:

Page 175. At the end of the first paragraph of subclause 10.8.1
[175:33] add
     The types of the items corresponding to an <r*c> input form may
     differ provided the whole of <c> is acceptable for each item.

SUBMITTED BY: Robert Corbett
HISTORY:  98-155   m145 Submitted (part 3)
          WG5/N1410     Draft answer