Vocabulary/scapco
>> << Down to: Dyad Back to: Vocabulary Thru to: Dictionary
[x] u S: n y Spread Conjunction
Rank Infinity -- operates on [x and] y as a whole -- WHY IS THIS IMPORTANT?
(u S:0 y) applies verb u to each leaf of y, creating an array whose items are the results of the leaves, with framing fill added as needed.
Contrast this with Level At (u L:0 y), which returns a result in which each leaf of y has been replaced by the result of executing u on it.
A leaf of y is a noun inside y that itself has no boxed contents.
A leaf is either empty or unboxed.
] y=: (<0 1),(<<2 3),(<<<4 5) +---+-----+-------+ |0 1|+---+|+-----+| | ||2 3|||+---+|| | |+---+|||4 5||| | | ||+---+|| | | |+-----+| +---+-----+-------+ NB. y is sample noun of nested boxed items NB. --The leaves are (0 1), (2 3) and (4 5) u=: |. NB. sample verb (Reverse) to apply to leaves u S:0 y 1 0 3 2 5 4
Compare this with the action of Level At (L:)
([x] u S:n y) applies u to the leaves of y in the same way as ([x] u L:n y) but it collects the results as the items of an array.
See Level At (L:) for details, including
- values of n other than 0
- negative values of n
- the dyadic case (x S: n y)
Common Uses
Apply verb u to the leaves (innermost opened items) of a boxed noun y
] y=: 'alpha' ; 'bravo' ;'charlie' +-----+-----+-------+ |alpha|bravo|charlie| +-----+-----+-------+ toupper S:0 y ALPHA BRAVO CHARLIE
Related Primitives
Level Of (L. y), Level At (u L: n)