which language allows you to change an argument's value?

[Jerry Stuckle]

Summercool wrote:
> On Sep 30, 4:18 am, 7stud -- <dol... at excite.com> wrote:
>> SpringFlowers AutumnMoon wrote:
>>> we have no way
>>> of knowing what we pass in could get changed.
>> Sure you do.  You look at the function's signature.  In order to use
>> someone else's library, you have to know the function's signature.  And
>> the signature explicitly tells you whether the value you pass in could
>> be changed.
> 
> do you mean in C++?  I tried to find signature in two C++ books and it
> is not there.  Google has a few results but it looks something like
> prototype.  Is signature the same as the function prototype in the .h
> file?  If so, don't we usually just include <___.h> and forget about
> the rest.  Documentation is fine although in some situation, the
> descriptions is 2 lines, and notes and warnings are 4, 5 times that,
> and the users' discussing it, holding different opinion is again 2, 3
> times of that length.  I think in Pascal and C, we can never have an
> argument modified unless we explicitly allow it, by passing in the
> pointer (address) of the argument.
>

You need to get more C++ books :-).  You generally won't find them in 
basic books, but some of the more advanced ones talk about function 
signatures.

A C++ function's signature is dependent on the function name, number of 
parameters being passed, and the type of each parameter.  This is passed 
onto the linker.  In any C++ program, every function signature must be 
unique.

But in this case he's a little incorrect.  You *could* look at the 
function's signature, but it's much easier just to look at the 
function's declaration.

> also i think for string, it is a bit different because by default,
> string is a pointer to char or the address of the first char in C and C
> ++.  So it is like passing in the address already.  it is when the
> argument n is something like 1 that makes me wonder.
> 
> 


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Jerry Stuckle
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