(j3.2006) J3 Fortran interp letter ballot #22 - due 19-Nov-2010
Mon Oct 18 03:39:23 EDT 2010
>> Being undefined is a property of a variable. IEEE_SUPPORT_DATATYPE is not a
>> variable, it is a function. A function reference (other than a
>> pointer-valued function) returns a value of the type. That does not include
>> the concept of being undefined.
> The "result variable" of a function is a variable.
However, we are talking about a function reference, not a reference to the
According to the definition of "defined" (or indeed "undefined"), it is a
concept that applies only to a data object, that is "constant, variable, or
subobject of a constant". That is conspicuously lacking any mention of
And since these are supplied by the compiler (being part of an intrinsic
module), there isn't any "result variable" anyway.
> I found where the standard requires a value to be assigned to a function's
> result variable. I suspect you're right that there is not a
> standard-conforming way to do that, and leave the result undefined.
Not only is there no standard-conforming way, there is no way at all since
*the result of evaluating a function reference is not a data object*
................................Malcolm Cohen, Nihon NAG, Tokyo.
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