This is a test of the order in which Scheme REPLs evaluate constant arguments. It doesn't necessarily apply when arguments have different levels of complexity, nor does it apply to compiled code. The test is ((lambda x x) (display "l") (display "t") (display "r")). In some cases, side-effecting procedures other than display were used.
Displays ltr: Racket, Gauche, Gambit, Chicken, Bigloo, Scheme48/scsh, Kawa, SCM, Vicare, Ypsilon, Mosh, IronScheme, NexJ, STklos, KSi, SigScheme, Scheme 9, RScheme, S7, Rep, Schemik, Elk, UMB, Llava, Sizzle, FemtoLisp, Dfsch, Inlab, Foment
Displays rtl: MIT, BDC, XLisp, SXM, Chibi
Unpredictable order: Chez
Undeterminable order (no side effects): Owl Lisp