#lang racket

> (foldl cons '() '(1 2 3 4 5 6))
'(6 5 4 3 2 1)
> (foldr cons '() '(1 2 3 4 5 6))
'(1 2 3 4 5 6)

#lang heresy
; join is Heresy's consing operator

> (foldl join '() '(1 2 3 4 5 6))
'((((((() . 1) . 2) . 3) . 4) . 5) . 6)
> (foldr join '() '(1 2 3 4 5 6))
'(1 2 3 4 5 6)