Hi Henry,

for the ANSI document on indexOfSubcollection:startingAt:,
i think that
'aaaaa' indexOfSubcollection: '' startingAt: 1 must return 1, not 0. (and if the argument is empty the starting index must be returned)

Message:� indexOfSubCollection: targetSequence startingAt: start
Synopsis
Answer the index of the first element of the receiver which is the start of a subsequence which
matches targetSequence. Start searching at index start in the receiver. Answer 0 if no such
subsequence is found.
Definition: <sequenceReadableCollection>
Each subsequence of the receiver starting at index start is checked for a match with
targetSequence. To match, each element of a subsequence of the receiver must be equivalent
to the corresponding element of targetSequence. Answer the index of the first element which
begins a matching subsequence; no further subsequences are considered. Answer 0 if no such
subsequence is found in the receiver, or if targetSequence is empty.
The elements are traversed in the order specified by the #do: message for the receiver.

The problem here is probably that subsequence definition is missing in the standard. If an empty sequence is allowed as argument then I think that the index must be the result. �Anybody has a formal definition of subsequence?

I don't know if the beginsWith: in SequenceableCollection must return true to #(1 2 3) beginsWith: #(), but for String I still think that must do.

Obviously there's some part of the protocol that should remain consistent. I will try to analyze that in deeper detail later.

Regards,
Gabriel

On Thu, Mar 4, 2010 at 11:27 AM, Henrik Johansen <henrik.s.johansen@veloxit.no> wrote:
Den 04.03.2010 14:40, skrev Julian Fitzell:
> I'm not sure, but in ANSI, indexOfSubcollection:startingAt: is defined
> as returning 0 (no match) for an empty collection.
>
If a string can not contain the empty string, then how can (and does) it
start/end with it?
IMHO, to be consistent, the set of what I contain should be a strict
superset of what I begin/end with.

In that regards, according to the ansi-standard, returning false is correct.

Cheers,
Henry

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