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Gerard and Alexander,
Ok, I agree with both of you.
It is just something I did not expect.
Yes, if I do LEN(y$) on the inside
and LEN(x$) on the outside then
I get the same results.
Thank you both.
-Doug
Gérard Meunier wrote:
> Douglas G. Danforth a écrit :
>>
>>
>> Gérard Meunier wrote:
>>> Douglas G. Danforth a écrit :
>>>> Folks,
>>>> I just discovered that the length of a string varies depending
>>>> upon whether it is used directly or passed as an argument to
>>>> a procedure for example
>>>>
>>>> VAR x: ARRAY 32 OF CHAR;
>>>> x := "HI";
>>>>
>>>> will have length
>>>> LEN(x$) = 2
>>>> but will have length
>>>> LEN(y) = 3
>>>> when it is passed to a procedure with argument y.
>> ...
>>> It's because you pass x$, and not x itself. x$ is the string inside
>>> the array of char, so its length is the length of the string plus 1
>>> (terminal 0X).
>>>
>>> Gérard
>> Ah, but if x$ is a "string" which you seem to imply includes the
>> terminal 0X then when I call
>> LEN(x$) in the outer procedure I should also get the value 3 and not
>> 2. There seems to be
>> an inconsistency.
> Here is how I see what happens: when x is passed to an IN parameter,
> its address is copied, so formal and actual parameters are identical;
> when x$ is passed, a new array of char is created, whose length is
> just enough to contain x$ (LEN(x$) + 1), x$ is copied into it and the
> new array is passed as actual parameter. In the last case, LEN(y$) =
> LEN(x$) and LEN(y) = LEN(x$) + 1.
>
> Gérard
>
> --- BlackBox
> --- send subject HELP or UNSUBSCRIBE to blackbox{([at]})nowhere.xy
>
>
--- BlackBox
--- send subject HELP or UNSUBSCRIBE to blackbox{([at]})nowhere.xy
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Received on Fri Sep 29 2006 - 21:15:11 UTC