Monadic close

Deactivates a reagent. If x is an IPC or TCP reagent, close closes the connection.

Syntax: close <x>; close [<x>]

whеre x is a reagent:

o)r:reagent[`async];
o)react {[x:r] 0N!x};
o)r[1]
1
o)meta r
id   | 3
state| `running
type | "async"
o)close[r]
o)meta r
id   | 3
state| `closed
type | "async"
o)r[2]
** I/O error: `reagent send`:
-- meta:
id   | 3
state| `closed
type | "async"
-- channel is closed