A tacit modifier cannot currently produce a fork as an arbitrary function
of its operands. (This is not the same thing as _implementing_ fork
tacitly. The modifier is still only a verb-producing adverb or
conjunction, but the resulting verb is a fork.)
AAV is closest thing currently, but its right tine is fixed, and the left
two cannot combine their operands with each other; so it must be nested
and combined with other trains; an exercise in verbosity and obfuscation.
Let me be more concrete. Given C0 C1 C2, I would like to be able to write
tacitly {{ (u C0 v) (u C1 v) (u C2 v) }}. (And the analogous adverbial
form, though that is obviously less important.)
In a 20-year-old thread referenced by Henry, Roger Hui says that forks and
atops are fundamental. But this is not quite right. f g h can be reduced
to [ (f g ]) h. Fork augments its root's left and right arguments
_separately_, which suggests a way out: fork is actually a combination of
two conjunctions (call them left fork and right fork). If they are
written [.. and ].., then f g h is simply shorthand for f ].. g [.. h.
Then my above conjunction becomes simple, pretty, and obvious:
C0 ].. C1 [.. C2
I think it generalises well. Hook is simply [. [.. (@]).
Compose is ]. ].. [. [.. ].--a bit noisy, but clear enough.
(Of course, it's not all sunshine and roses. For consistency with the
mistakes of @, &, and &., ].. and [.. should take on the relevant parts
of the augmenting verb's rank, with ]..: and [..: as infinitely-ranked
counterparts. But perhaps we can skip that this time? :)
-E
P.S. I will also note an incidental argument in favour of conjunctive
hooks. If h is the 'hook' conjunction then, as V0 V1 is shorthand
for V0 h V1, so is C0 C1 shorthand for C0 h C1. This remains
relevant even if h is redefined to be saner.
P.P.S. Also nice would be a higher-order constant function. A constant
verb can be written as m"_; and a constant adverb as (a[.) or
(].a). A constant conjunction must be a[.junk or junk].a, where
junk is a useless conjunction or adverb.
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