(j3.2006) Interp F03/0091

[Van Snyder]

Malcolm has pointed out to me in private that the decision reached in
plenary on Friday at 180 contradicts 4.5.3.1, which says that a
component that has a <component-array-spec> or the DIMENSION attribute
is an array.  If its dimensions aren't colons, what kind of array is it?
The only one that fits is an explicit shape array.  Maybe the words that
introduce 5.1.2.5.1 need some polishing to include components, because
otherwise array components that aren't deferred-shape arrays are no kind
of array at all.  Then C542 needs to be repaired as originally suggested
to allow the bounds of explicit-shape array components to depend upon
length parameters of the type being defined.

Van

>                                                              07-232
> To:      J3
> From:    Michael Ingrassia
> Subject: Array components cannot depend on length type parameters
> Date: 2007 May 10
> 
> NUMBER:   F03/0091
> TITLE:    Array components cannot depend on length type parameters
> KEYWORDS: length parameter, specification expression, component
>           declarations
> DEFECT TYPE: Erratum
> STATUS:   J3 consideration in progress
> 
> QUESTION:
> 
> Consider
> 
>   MODULE m
>     TYPE t(n)
>       INTEGER,LEN :: n
>       REAL v(n)
>     END TYPE
>   END
> 
> According to C542 at [78:21-22], the bounds in that <explicit-shape-spec>
> are required to be initialization expressions.  That seems to prevent the
> intended use of length type parameters.
> 
> Is the example intended to be standard-conforming?
> 
> ANSWER:
> 
> Yes, the example was intended to be standard-conforming.
> Constraint C542 does not actually apply since v(n) is not an explicit-shape 
> array as defined at [78:16], but is instead an array component as
> described in 4.5.3.1.  The syntax for both explicit-shape arrays and
> array components currently is derived using the same
>  term explicit-shape-spec from the BNF.
> 
> 
> EDITS: Constraint 542 should refer to syntax rule R510 instead of syntax
> rule R511, making [78:21] read
> 
> > C542  (R510) An explicit-shape array ...
> 
> 
> 
> SUBMITTED BY: Van Snyder
> 
> HISTORY: m180 07-231   submitted as modified by Malcolm Cohen.
> 	 m181 07-231r1 submitted as modified by Michael Ingrassia / Jim Xie
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