Each-prior and monad

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1

Per each prior ; the definition says v2 ( dyad verb) then how the does the monad below work ?

f:{:(~)x} / unary function
({(~)x}‘:) 0 1 2 3 / output is 1000b
({(~)x}’:) (,)0  /output is enlist 1b

2

That’s also parallel each, i.e. the k adverb is overloaded. It has different keywords in q for the monadic and dyadic case:
q) prior ~ peach

1b

András

3

': means peach when applied to monadic functions https://code.kx.com/q/ref/maps/#each-parallel. 

So what you have is:

not peach 0 1 2 3

not peach enlist 0

4

This is not each prior in this case, it is each-parallel/peach. And if you don’t have slaves configured the each-parallel is likely defaulting to each. Same as

q)not each 0 1 2 3

1000b

You can confirm it’s an each-parallel by attempting to set a global (with slaves enabled):

q)({`a set 1;(~)x}':)0 1 2 3

'noupdate: . a

[1] (.q.set)


[0] {`a set 1;(~)x}

^

Terry