I tested the usual suite of Schemes with '[a b c]
to see how they reacted to the square brackets.
R6RS requires the result to be (a b c).
R6RS, so evaluates to (a b c): Racket, Guile, SISC,
Vicare, Larceny, Ypsilon, Mosh, IronScheme, Sagittarius
Non-R6RS but evaluates to (a b c): Gauche, Gambit, Chicken, Bigloo, SISC,
Scheme 9, STklos, KSi, Schemik, Elk, Oaklisp,
SXM, Sizzle, Spark
Evaluates to the symbol [a, followed by undefined-variable error on b:
Chibi, SCM, Shoe, TinyScheme, Dream, S7, BDC, XLisp, UMB, VX, Llava, Dfsch, Inlab
Syntax error: MIT, Scheme48/scsh, NexJ, SigScheme, RScheme, Owl Lisp
Evaluates to #(a b c): Rep, FemtoLisp
Evaluates to ($bracket-list$ a b c): Kawa