macro
boot.janet on line 1484 , column 1
(as-> x as & forms )
Thread forms together , replacing `as` in `forms` with the value of
the previous form. The first form is the value x. Returns the last
value.
(as-> [1 2 3 ] _
(map inc _ )
(sum _ )
(- _ 10 )
(< _ 0 ))
# -> true
# same as
(< (- (sum (map inc [1 2 3 ])) 10 ) 0 )