offset broken?

[Peter Haworth]

Hi Bill,
If you specify a number of characters to skip, the offset that is returned
is relative to that number, not the start of the string.  So if you specify
7 characters to skip and the character you are looking for is the 10th
character in the string, you will get (10-7) or 3 as the result.

Pete
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On Sat, Feb 22, 2014 at 9:49 AM, prothero at earthednet.org <
prothero at earthednet.org> wrote:

> Folks:
> I think there is something weird about "offset". This occurred on version
> 6.5 and now on 6.6.
>
> First off, the documents say:
>
> "the charsToSkip is a non-negative integer. If you don't specify how many
> charsToSkip, the offset function does not skip any items and starts at the
> beginning of the stringToSearch."
>
> Note the use of the word "items".  Skipping characters vs skipping "items"
> is a different matter. In the revdocs that are online, the definition of
> "characters" to skip is correct.
>
> But, that's not the end of the story. Offset does not appear to be working
> correctly anyway.
>
> If I run the script:
>
>    put "abcdefgabcccablmnopoq" into theChars
>    put offset("c",theChars)
>
> I get: 3, which is correct
>
> If I do:
>    put "abcdefgabcccablmnopoq" into theChars
>    put offset("c",theChars,3)
>
> I get 7.  ??? What the heck? It looks like it returns (the number of
> characters to the search char) - (# to skip).
>
> But, if I do:
>    put "abcdefgabcccablmnopoq" into theChars
>    put offset("c",theChars,7)
>
> I get: 3
>
> So, something is very wrong with the offset command. I worked around this
> in a parsing script by always not skipping any characters, then after I
> found the first instance, deleting the characters I wanted to skip before
> the next offset invocation.
>
> Seems like a bug to me. What do you think? Or is it only my system? Or is
> the use of the offset function some convoluted logic that's different from
> most other implementations of an offset function? What do I know? I'm new
> to Livecode.
>
> Best,
> Bill
>
>
> William Prothero
> http://es.earthednet.org
>
>
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