On Mon, Jul 27, 2009 at 8:01 AM, Dan Bron<[email protected]> wrote:
> So, instead, I've given the user the ability to select his own
> "end of strand" marker. Or, rather "beginning of strand" marker:
>
> | 'this is' 4 'words' 'of strand notation' s|
> +-------+-+-----+------------------+
> |this is|4|words|of strand notation|
> +-------+-+-----+------------------+
Let us imagine you could pick an arbitrary word to
mark the end of a strand. Perhaps 'end'. (I am
going to reject ideas like getting rid of the current
definitions of tokens, because that does not work in
any current version of J -- I hope you do not mind.)
Then, you could do something like this:
] 'a' 2 'b' 3 'c' end
+-+-+-+-+-+
|a|2|b|3|c|
+-+-+-+-+-+
I do not know if this mechanism is desirable,
but it seems easy enough to implement:
continuestrand=:2 :0
if.nc<'u' do.
u n
else.if.L.n do.
continuestrand(m;n)
else.
continuestrand(<m)
end.end.
)
end=:continuestrand''
Note: In reality, the "end of strand" mechanism,
here, is the verb on the far left. Remember that
J's parser consumes its queue from right to left.
I have arbitrarily decided that the "end of strand"
word must be a monadic verb, and that the result
of the strand as a whole is the result of that verb.
--
Raul
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