Roger wrote:
> It is possible to avoid any use of 10| at all:
>
> sna =: 841 $ '0987654321'
> guard=: sna {~ 1 3 1 7 3 9 +/ .*~ sn i. ]
Some experiments show that x&i. doesn't do any special magic when #x is
large yet #~.x is small. But it could.
(That is, there could be special code to handle the case that the x in x&i.
is a large number of repetitions of a small
universe, so that the entire of x needn't be scanned for each lookup).
Unless I did my experiments wrong.
-Dan
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