Re: Null Range in Unconstrasined Array

["Randy Brukardt" <randy@rrsoftware.com>]

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"Rick" <rickduley@gmail.com> wrote in message 
news:f237670b-ade0-461f-9d02-5eff803e91bc@p10g2000prm.googlegroups.com...
>If I have an unconstrained array type 'My_Array_Type' and declare an
>instance of it as:
>
>My_Array : My_Array_Type (1 .. 0);
>
>then the LRM tells me it is a null range:
>
>3.5 (4): A range with lower bound L and upper bound R is described by
>�L .. R�. If R is less than L, then the range is a null range, and
>specifies an empty set of values.
>
>What, exactly, is My_Array (forgive the language) pointing to?
>Is any memory allocated to My_Array?

That's a question that the ARG decided not to answer in general. (It matters 
for aliased objects and "=" of accesses to such objects). We agreed to not 
decide (see AI95-00350-1, voted No Action). It seems silly to require 
allocating memory for objects with no components, but some people think that 
it is important that access type compare unequal. Thus there was no 
agreement on clarifying the wording.

So you'll have to look to see what your particular compiler does.

                                                              Randy.