Re: [BLACKBOX] Read-only IN parameters for all data types

From: Campbell, Robert (SELEX GALILEO, UK) <"Campbell,>
Date: Wed, 20 Feb 2008 08:54:50 -0000

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>> -----Original Message-----
>> From: BlackBox [mailto:BLACKBOX{([at]})nowhere.xy
>> Of CFB Software
>> Sent: 19 February 2008 23:42

>> NOTE: I stated above that IN parameters are *used* as value
>> parameters - whether the compiler writer *implements* them
>> as value, refererence or whatever for efficiency reasons
>> should not be something that the programmer should need to
>> be aware of - as long as the parameters *behave* as defined).
>>
>> Passing a pointer as an IN parameter could be viewed as
>> another example of side-effects. I have not been able to
>> think of a feasible way to protect IN parameters from
>> modification by side-effects as shown by Robert Campbell in
>> his Horrible example recently.


Chris

I can't remember the precise details (and I have thrown 'Horrible'
away!),
but I thought that the point is that to make Horrible predictable we
*do*
need to know if the parameter is passed by value or reference.

I accept that in 'sane' use we do not.

Regards

Robert

SELEX Sensors and Airborne Systems Limited
Registered Office: Sigma House, Christopher Martin Road, Basildon, Essex SS14 3EL
A company registered in England & Wales. Company no. 02426132
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Received on Wed Feb 20 2008 - 09:54:50 UTC