F&O: subsequence and item-at

Hello,

concerning the subsequence function I would suggest to specify it
similary to substring. This would be consistent and answer such
questions like "what if $startingLoc is negative" etc.

Additionally, item-at($seq, $pos) should IMO return the same as
subsequence($seq, $pos, 1)
i.e. instead of raising an error "Invalid position" this function
would return the empty sequence if $pos is out of bounds.
This poses the question if item-at is necessary at all, since
subsequence($seq, $pos, 1) would do the task.

Kind regards,
Oliver


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|  ob|do        Dipl.Inf. Oliver Becker                             |
|  --+--        E-Mail: obecker@informatik.hu-berlin.de             |
|  op|qo        WWW:    http://www.informatik.hu-berlin.de/~obecker |
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Received on Monday, 20 January 2003 10:23:26 UTC