cons list constructor List i Object x Object Creates a new cons cell whose head is i and tail is x (cons 'a '(b)) => (a b) (cons 'a 'b) => (a . b) list list constructor List val1 Object ... valn Object Creates a list from a variables number of arguments (list 1 2 3) => (1 2 3) (list 1 (* 2 1) (+ 2 1)) => (1 2 3) range list constructor List start Number end Number [interval] Number Builds a list ranging from start to end, inclusive. The interval can be ommitted, and defaults to 1.0 (range 1 5) => (1 2 3 4 5) (range 1 2 0.2) => (1.0 1.2 1.4 1.6 1.8 2.0) head list accessor Object x List Returns the head (first item) of list x (head '(a b c)) => a tail list accessor Object x List Returns the tail (all items except first) of list x (tail '(a b c)) => (b c) take list func List i Number s Sequence Returns the first i elements of s (take 3 '(a b c d e)) => (a b c) (take 3 "woof") => "woo" drop list func List i Number s Sequence Returns the sequence s without the first i elements (drop 3 '(a b c d e)) => (d e) (drop 3 "woof") => "f" def env Object sym Symbol val Object Binds sym to evaluated val in the current scope, returns val (def x 3) => 3 (do (def y 1) (-- y) y)) => 0 let env Object sym Symbol val Object ... code Object Binds sym to val in a nested scope, evaluates code (let i 3 (print i)) => nil ;;prints 3 (do (let i 3) (print i)) => error: unbound symbol i let env Object ((sym1 Symbol val1) Object ... bindings) Object ... code Object The scheme-like syntax for let, binds multiple symbols and evaluates code (let ((i 0)(j 2)) (+ i j)) reverse list func List x List Returns the sequence x in reverse order (reverse '(a b c)) => (c b a) member? list func Boolean a Object c Container Returns true if a is in container c, false otherwise (member? 'x '(x y z)) => #t (member? \a "waffle") => #t (member? \a "wolf") => #f remove list func Sequence a Object c Container Returns container c excluding every instance of object a (remove 'muppet '(wolf baby muppet muppet)) => (wolf baby) (remove \c "clock") => "lock") splice list func Sequence a Sequence b Sequence Combines two sequences into one (splice '(a b) '(c d)) => (a b c d) (splice "angry" "hyrax") => "angryhyrax" eval eval Object expr Object Evaluates the argument, returns the result (eval '1) => 1 (eval '(+ 1 1)) => 2 (eval 'cons) => compiled-fn: (any any) quote eval Object expr Object Returns argument unevaluated, can also be written as a single-quote: ' (quote x) => x 'x => x '(+ 1 2) => (+ 1 2) do eval Object ... code Object Evaluates a code sequence in the current scope, returns the last evaluated value (do (+ 1 2) (+ 1 3)) => 4 local eval ... code Object Creates a local nested scope in which it evaluates a code sequence (local (def i 0) (+ i 1)) => 1 (do (local (def i 0) ) (+ i 1) => error: unbound symbol i if eval Object b Boolean exprT Object [exprF] Object If b is true then exprT is evaluated, else exprF is evaluated. If exprF is omitted, then #f is returned (if #t 1 2) => 1 (if (= 0 7) 'x 'y)) => y (if #f 1) => #f apply higher order Object f Procedure argslist List Apply argslist to function f, returns the evaluated result (apply + '(1 1)) => 2 (apply + '(1)) => error: arity mismatch, function + expects 2 arguments partial-apply higher order Function f Function arg1 Object ... argn Object Partially evaluates function f (of arity m) for given arguments, returns a function of arity m-n (partial-apply + 1) => fn (number) ((partial-apply + 1) 1) => 2 ((partial-apply cons ? '(b c)) 'a) => (a b c) map higher order Collection f Function c Collection ... cn Collection Passes each member of c to f and builds a list from the results (map sqrt '(4 9 16 25 36)) => (2 3 4 5 6) (map odd? '(1 2 3 4)) => (#t #f #t #f) (map + '(1 2 3 4) '(2 3 4 5)) => (3 5 7 9) filter higher order Collection p Function c Collection Applies the predicate p to every member of c, returns a collection of those members for which p was true. (filter odd? '(1 2 3 4)) => (1 3) (filter (fn (x) (= x 1)) '(1 2 1)) => (1 1) reduce higher order Object f Function c Collection Applies f pairwise to the elements of c, reducing the collectionto a single value (reduce + '(1 2 3)) => 6 (reduce + '(1)) => 1 (reduce + '()) => error: list must not be empty type type func Symbol x Object Returns the type of any object (type 1) => int (type 1.0) => float (type '(a b c)) => list (type "gerbils") => string (type cons) => compiled-fn (any any) (type (fn (x) x)) => closure (any) subtype? type func Boolean s Symbol t Symbol Returns true if s is a subtype of t, false otherwise (subtype? (type 3.0) 'number) => #t (subtype? 'list 'list) => #t isa? type func Boolean s Symbol t Symbol Accepts an object s and a type t, returns true if the the type of s is a subtype of t (isa? 1 'number) => #t (isa? cons 'list) => #f new type func Object type Symbol ... args Object Creates a new instance of a specified type, passing args to the type constructor (new 'int 1) => 1 (new 'int) => error: args list () does not match constructor for int: (num) (new 'vector 1 2 3) => <1 2 3> while iter Object cond Object ... code Object Repeatedly tests the condition, and while it is true evaluates code (let x 3 (while (not (= x 0)) (-- x) (print x))) => nil ;;prints 321 until iter Object cond Object ... code Object Repeatedly evaluates code until condition is false. Returns the value of code from last iteration (let x 0 (until (= x 10) (++ x))) => 10 dotimes iter Object n Integer ... code Object Evaluates code n times (dotimes 5 (print \x)) => nil ;;prints: xxxxx for iter Object init Object test Object update Object code Object Similar to the C++ for loop, evaluates in a nested namespace (for (def i 0) (< i 5) (++ i) (print i)) => nil ;;prints 12345 foreach iter Object i Symbol c Container ... code Object Iterates over contents of c, assigns i to the value of each element and evaluates code (foreach x '(1 2 3) (print x)) => nil ;;prints 123