A conjunction that returns an adverb and applies its 2 arguments before and
after the adverb's parameter.
B =: 2 : '(@: u)(v @:)'
>: +:B -: 2
2.5
>: &.+: 2
2.5
>: dfh B hfd '1a'
1b
The verbs are placed counterintuitively under the presumption that the u verb
will be longer, and so this avoids parentheses. Also the u side is what
modifies the adverb parameter.
dfh and hfd are not defined as inverses, and this also lets you setup up
bracketed operations independently of they being inverses.
A bit more complex of a between conjunction, where the closer also uses the
same y parameter (as its x):
Bwy =: 2 : ' 1 : (''] ('' , v lrA , '') [: '', '' u ('' , (u lrA) ,'')"_'')'
sfX =: 1 : '][u' NB. apply u, but keep y as the result.
+: +:Bwy(-~)
] -~ [: +: +:"_
+: +:Bwy(-~) 2
6
for a useful example,
'1' fwrite jpath '~temp/1.cnt'
1
withFile =: &.". fread Bwy (fwrite~ sfX) NB. adverb that will apply operation
to file then save it.
>: withFile
] (] [ fwrite~) [: >:&.". fread"_
>: withFile jpath '~temp/1.cnt'
2
Another bracketing type application is for "ensure even if error" code. Can't
seem to decide what should be u and v, as this is inverted compared to above:
BetweenE =: 2 : ' 1 : (''([: ('' , u lrA , '') [: '', '' u ('' , (v lrA)
,'')"_) :: ('' , u lrA , '')'' )'
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