macro
boot.janet on line 1147, column 1
(-?> x & forms)
Short circuit threading macro. Inserts x as the second value in the
first form in forms, and inserts the modified first form into the
second form in the same manner, and so on. The pipeline will return
nil if an intermediate value is nil. Useful for expressing pipelines
of data.
(defn return-nil [x] nil)
(-?> 1 inc) # -> 2
(-?> 1 inc inc) # -> 3
(-?> 1 inc inc return-nil) # -> nil
(-?> 1 inc inc return-nil inc) # -> nil