RE: substring: explanation of negative or zero $startingLoc behaviour

What would help me I think is an explanation of what a negative position
means.
Howard

> -----Original Message-----
> From: Michael Kay [mailto:mhk@mhk.me.uk]
> Sent: Friday, March 12, 2004 10:27 AM
> To: 'Howard Katz'; public-qt-comments@w3.org
> Subject: RE: substring: explanation of negative or zero $startingLoc
> behaviour
>
>
> The definitive statement in the spec is:
>
> More specifically, returns the characters in $sourceString whose
> position $p
> obeys:
>
> fn:round($startingLoc) <= $p < fn:round($startingLoc) + fn:round($length)
>
> The subsequent paragraphs are just trying to be helpful, and
> apparently not
> succeeding.
>
> Michael Kay
>
> # -----Original Message-----
> # From: public-qt-comments-request@w3.org [mailto:public-qt-comments-
> # request@w3.org] On Behalf Of Howard Katz
> # Sent: 12 March 2004 18:08
> # To: public-qt-comments@w3.org
> # Subject: fn:substring: explanation of negative or zero $startingLoc
> # behaviour
> #
> #
> # F and O: 7.4.3 fn:substring()
> #
> # The explanation of $startingLoc in 7.4.3 reads, "If $startingLoc is zero
> # or
> # negative, the substring includes characters from the beginning of the
> # $sourceString." I find the meaning of the phrase "from the beginning of
> # the
> # $sourceString" to be unclear and can't find any other reference to the
> # concept of negative character positions within a string.
> #
> # Out-of-band communication on the www-ql list seems to indicate that the
> # concept of "imaginary character positions" preceding the
> physical start of
> # the string might be a useful way of explaining zero or negative
> # $startingLoc
> # behaviour. I'd suggest the addition of this or a similar explanation to
> # 7.4.3.
> #
> # Howard
>
>

Received on Friday, 12 March 2004 13:39:12 UTC