You can do whatever you need without Fold, but it has these features:
* iteration can be forward or backward through items of a noun
* initial value can be provided as its own argument
* early termination is allowed
* either one result for the whole iteration or a result item per iteration
** result of an iteration can be a subset of the complete internal state
passed to the next iteration
** results of individual iterations can be put into the overall result
or not
* iteration can be by item or on the entire argument until a condition
is met
Henry Rich
On 3/28/2020 6:25 PM, Devon McCormick wrote:
Hi -
I noticed the "fold" conjunctions only recently. However, I was under the
impression that J already has ways to accomplish what is meant by different
kinds of folds - see
https://en.wikipedia.org/wiki/Fold_%28higher-order_function%29#In_various_languages
.
Can someone involved with the "F" conjunctions explain their rationale?
Thanks,
Devon
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