"&" is from C, I believe is "passing the address of", sorry,

On the other hand, the Pascal keyword

VAR

is described by Grogono in "Programming In Pascal" (c) 1978; pg 28;  
syntax for variable declarations; pg 91 VAR paramaters, pg 94 syntax  
for a parameter list.

I also have "Pascal" by Chirlian from 1980 - same deal, different  
pages... 37 and 127.

My pascal path began with Honeywell (they transitioned from assembler  
to Pascal in 1978, my third year with them), since then I have used  
Apple USCD, Microsoft ISO, MPW, CodeWarrior, and now Free Pascal.  
Somewhat focused on Mac, I must admit.

Developed apps and even taught the language for a year... hence not  
one but two ready textbooks for references.... spooky.

Here is a Mac Pascal file system read call illustrating several  
features:

FUNCTION FSRead(refNum: INTEGER; VAR count: LONGINT; buffPtr: UNIV  
Ptr): OSErr;

VAR indicates that count can be modified. The API documentation for  
FSRead describes "count" as both input as a number of bytes desired  
and output as the number of bytes actually read. The keyword UNIV is  
a Mac-Pascal extension to opaque the Ptr receiving the data.

Of course, in today's implementations, one should first consider  
raising an exception rather than return an error.

This call illustrates multiple (three) returned variables, one of  
type LONGINT, second, the modified contents of the memory block  
buffPtr is looking at and the third, an error code of type OSErr (an  
INTEGER).

How did VAX declare variables?

Gary



On Mar 24, 2007, at 6:42 AM, Karen wrote:

>
> On Mar 24, 2007, at 6:00 AM, M Pulis wrote:
>
>>
>> Yep... Pascal (1978 to present) here - works just as well as any
>> coding... as long as intent is well documented, whether "BYREF" or
>> "VAR" or "&", they mean the same, simply a parameter defined as
>> capable of both input and output.
>>
>
>
> I used VAX Pascal in the 80's and I don't recall VAR and "&"
>
>
> - Karen
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