To me, forks and trains are part of the right to left grammar, so your question
really puzzles me! Something like
([: %: [: +/ *:) 3 4 NB. The square root of the sum of squares of 3 4
5
is parsed right to left as described in the Parsing and Execution section II.E
of the Dictionary, http://jsoftware.com/help/dictionary/dicte.htm . When I
parse it myself, I think
OK, 3 4 is a vector, what does the parentheses do? Seeing a train, I must
group
from the right, first [: +/ *: which is the sum of squares, next
[: %: the-sum-of-squares which is the square root of the-sum-of-squares.
Finally, apply the-square-root-of-the-sum-of-squares to 3 4, getting 5.
Experts will tell me I could have done
(+/ &.: *:) 3 4
5
where the parentheses is not a train because the central element is a
conjunction. The result of ([: %: +/ &.: *:) 3 4 is the square root of 5 :
([: %: +/ &.: *:) 3 4
2.23607
Kip Murray
Don Watson wrote:
> Tacit J and the verb compositions, including forks and hooks
> have significant advantages. However, there is one question that
> really puzzles me.
>
> When longer trains of verbs (and other language components) are
> created in Tacit J, why is the fork/hook grammar better than
> right to left grammar?
>
> I haven't come across any explanation of the reason for the
> change in grammar.
>
> Don
>
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