Re: Selecting the first item from a tokenized string

David Carlisle wrote:

>    Michael Kay wrote:

>    > you can get the Nth item in a sequence using SEQ[N].
>    > In the rare cases where that's inconvenient because
>    > it changes the evaluation context, you can use
>    > subsequence(SEQ, N, 1).

>      When can this happen?  Can you show an example?

> SEQ[N]
>   selects the first and third SEQ
>   (as they have N children)

> SEQ[number(N)]
>   selects the third SEQ
>   (as that is the only one with an N child equal to its
>    position())

> subsequence(SEQ,N,1)
>   selects the 2nd SEQ child
>   (as N selects an element whose value can be cast to the
>    integer 2.)

  Ok, thanks for your response.  It helps me to understand where I
think I misunderstood Michael.  Where he said

    in the rare cases where that's inconvenient
    because it changes the evaluation context

I undesrtood something like:

    in the rare cases where it changes the
    evaluation context (so that becomes
    inconvenient)

where the intended meaning was, I think now:

    in the rare cases where that's inconvenient
    because the evaluation context change
    (anyway, that always changes the evaluation
    context)

  Right?  Please blame my poor english.

  Sorry for the noise.  Regards,

--drkm



















	

	
		
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