[fpc-pascal] conformant arrays and Free Pascal

[Mehmet Erol Sanliturk]

Michael Van Canneyt wrote:
> 
> 
> On Fri, 6 Nov 2009, Jonas Maebe wrote:
> 
>>
>> On 06 Nov 2009, at 09:03, Michael Van Canneyt wrote:
>>
>>> Can you give us some more info on conformant arrays ? It's the first 
>>> time I heard of such a construct.
>>
>> http://docs.hp.com/cgi-bin/doc3k/B3150290023.10194/53
> 
> Hmmm.
> Does not sound like something easily supported :(
> 
> Michael.
> 




In the book


A Model Implementation of Standard Pascal

by
Jim Welsh and
Atholl Hay

PRENTICE/HALL INTERNATIONAL
ISBN : 0-13-586454-2
1986

the Conformant Arrays are implemented .
( page 92 : 9.10 Conformant array handling )


( Standard Pascal means a Pascal defined by Standards BS 6192 and ISO 
7185 . )

In its Foreword it is written

´Firstly it places in the public domain a complete implementation of the 
International Standard for the PASCAL programming language . ´
( p. vii )


I think , in a Pascal compiler
ability to define an array like the following


Procedure X
       (
       m : Integer ;
       n : Integer ;
       p : Integer ;
       q : Integer ;
   Var a : Array [ m .. n , p .. q ] of Real ;
       ...
       ) ;

will make it very usable in scientific computations like Fortran having
run time Dimension statement .

Here , the most important part is to use m , n , p , q as VARIABLES 
taking values at run time .



At present , when m , n , p , q are constants , the following statement 
is compiled :



Const  m = 1 ;
Const  n = 20 ;
Const  p = 0  ;
Const  q = 45 ;


Procedure X
       (
   Var a : Array [ m .. n , p .. q ] of Real ;
       ...
       ) ;


A similar part will be inserted into compiled code to be used in run time .



Thank you very much

Mehmet Erol Sanliturk