[fpc-devel] fpc_pchar_length error
alexandru.alexandrov at gmail.com
Mon Dec 12 14:29:03 CET 2005
On 12/12/05, Michael Van Canneyt <michael at freepascal.org> wrote:
> On Mon, 12 Dec 2005, Jonas Maebe wrote:
> > On 11 dec 2005, at 22:22, Alexandrov Alexandru wrote:
> >>> It depends on the specs of "length" :-)
> >> What do you mean with specs?
> > How it is defined to behave in the documentation (i.e., whether the
> > documentation says "if you call length with as argument a nil pointer, the
> > result is defined to be 0", or "the behaviour of length with as argument a
> > nil pointer is undefined", or simply doesn't mention it at all).
> >> btw i forgot to mention, i tested on winxp.
> >> In Delphi the result is 0, and no error.
> > Delphi obviously is a lot more tolerant to bad programming than we are... A
> > pchar which is nil is not an empty string, but an invalid pointer. It's like
> > assuming that a nil pointer to a longint is the same as a pointer to the
> > value 0 or so.
> I agree with this position.
> A Nil pointer is usually a sign of a bad or uninitialized value.
..but we speak here about the length of the string. IMO the length of
null string is the same as the length of an unitialised string.
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