The UnderFrom adverb evaluates verb u on x{y and replaces x{y with the
result. (In c, array notation y[x] = u(y[x]) What problems ensue from
implementing an obverse to from?
UnderFrom =: (@:{)(`[)(`])}
3 ^.UnderFrom i._8 NB. ln of the fourth item
7 6 5 1.38629 3 2 1 0
NB. under from
3 ^.&.{ i._8
|domain error
| 3 ^.&.{i._8
^.&.(3&{) i._8
|index error
| ^.&.(3&{)i._8
I hope this is a better idea than the marginally useful global `for'
assignment which I would occasionally use to debug. for_i: do. end.
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