Composite item (represented by the curly right brace character) is described as an adverb because m} is a verb which has rank.
The verb 0 1 0 1 0} for example can be used monadically, as you demonstrate at the beginning of your message. It can also be used dyadically, though that makes less sense (since there's no useful semantics associated with repeating the indices 0 and 1 in the dyadic context). But, it works, at least for some concept of "works": 'ABCDE' 0 1 0 1 0} 'abcde' EDcde Similarly, with "insert" a verb of the form +/ has a dyadic meaning (though that meaning is perhaps not well described by the word "insert"): 0 1 +/2 3 4 2 3 4 3 4 5 Anyways, ... the "verb" being "modified} by "composite item" might be best described as the indexing operation implied by the existence of indices. Formally, the phrase has grammar noun adverb rather than verb adverb, but sometimes it helps to use analogies. I hope this makes sense? -- Raul On Thu, Jan 6, 2022 at 11:09 PM Arthur Anger <[email protected]> wrote: > > 1. Syntactic confusion > 0 1 0 1 0 } 'abcde' ,: ' ' > a c e > ( 0 1 0 1 0 } ] ,: ' '&[) 'abcde' > abcde > abcde > ( 0 1 0 1 0&[ } ] ,: ' '&[) 'abcde' > |domain error > | (0 1 0 1 0&[}],:' '&[)'abcde' > ( [: 0 1 0 1 0 } ] ,: ' '&[) 'abcde' > a c e > ( [ 0 1 0 1 0 } ] ,: ' '&[) 'abcde' > abcde > abcde > > 2. Why is Composite item described as an adverb? > The note on its rank even refers to an operand x. (As happens also for > Insert, where there can be no x.) > What verb is it modifying in the next-to-last sample above? > > Thanks for any clarification. > --Art > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
