func Read(b *bufio.Reader) (goscm.SCMT, error) {
err := chomp_meaningless(b)
if err != nil {
return goscm.SCM_Nil, err
}
c, err := b.ReadByte()
if err != nil {
return goscm.SCM_Nil, err
}
switch {
case c == '(':
// A list
return read_list(b)
case c == ')':
// Unbalanced list
return goscm.SCM_Nil, errors.New("Mismatched parenthesis")
case c == '\'':
// A piece of quoted syntax
subexpr, err := Read(b)
if err != nil {
return goscm.SCM_Nil, err
}
return goscm.NewList(
goscm.NewSymbol("quote"),
subexpr), nil
case c >= '0' && c <= '9':
// An integer
b.UnreadByte()
return read_integer(b)
case c == '"':
// A string
return read_string(b)
case c == '#':
// Something special, but for simple just a bool
return read_bool(b)
default:
// A symbol
b.UnreadByte()
return read_symbol(b)
}
}
func scm_map(args *goscm.Pair, env *goscm.Environ) (goscm.SCMT, error) {
argss, err := args.ToSlice()
if err != nil {
return goscm.SCM_Nil, err
}
if len(argss) < 2 {
return goscm.SCM_Nil, errors.New("Too few arguments")
}
if len(argss) > 2 {
return goscm.SCM_Nil, errors.New("Too many arguments")
}
proc, ok := argss[0].(goscm.Func)
if !ok {
return goscm.SCM_Nil, errors.New("Non-function in first position")
}
if reflect.TypeOf(argss[1]) != reflect.TypeOf(&goscm.Pair{}) {
return goscm.SCM_Nil, errors.New("Expected pair")
}
tail, err := argss[1].(*goscm.Pair).ToSlice()
if err != nil {
return goscm.SCM_Nil, err
}
ret := goscm.SCM_Nil
for i := len(tail) - 1; i >= 0; i-- {
result, err := proc.Apply(goscm.NewList(tail[i]), env)
if err != nil {
return goscm.SCM_Nil, err
}
ret = goscm.Cons(result, ret)
}
return ret, nil
}
func Test_Env(t *testing.T) {
env := Env()
// Test define
goscm.NewList(
goscm.NewSymbol("define"),
goscm.NewSymbol("a"),
goscm.NewSCMT(1234),
).Eval(env)
a_result, err := goscm.NewSymbol("a").Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(a_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(a_result))
}
if a_result.String() != "1234" {
t.Error(a_result)
}
// Test +
add_result, err := goscm.NewList(
goscm.NewSymbol("+"),
goscm.NewSCMT(321),
goscm.NewSymbol("a"),
goscm.NewSCMT(222),
goscm.NewSCMT(1000),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(add_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(add_result))
}
if add_result.String() != "2777" {
t.Error(add_result)
}
// Test -
sub_result, err := goscm.NewList(
goscm.NewSymbol("-"),
goscm.NewSCMT(100),
goscm.NewSCMT(9),
goscm.NewSCMT(90),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(sub_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(sub_result))
}
if sub_result.String() != "1" {
t.Error(sub_result)
}
// Test *
mult_result, err := goscm.NewList(
goscm.NewSymbol("*"),
goscm.NewSCMT(1),
goscm.NewSCMT(2),
goscm.NewSCMT(3),
goscm.NewSCMT(4),
goscm.NewSCMT(5),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(mult_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(mult_result))
}
if mult_result.String() != "120" {
t.Error(mult_result)
}
// Test /
div_result, err := goscm.NewList(
goscm.NewSymbol("/"),
goscm.NewSCMT(66),
goscm.NewSCMT(3),
goscm.NewSCMT(2),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(div_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(div_result))
}
if div_result.String() != "11" {
t.Error(div_result)
}
// Test cons
cons_result, err := goscm.NewList(
goscm.NewSymbol("cons"),
goscm.NewSCMT(2),
goscm.NewSCMT(5),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(cons_result) != reflect.TypeOf(&goscm.Pair{}) {
t.Error(reflect.TypeOf(cons_result))
}
if cons_result.String() != "(2 . 5)" {
t.Error(cons_result)
}
// Test car
car_result, err := goscm.NewList(
goscm.NewSymbol("car"),
goscm.NewList(
goscm.NewSymbol("cons"),
goscm.NewSCMT(333),
goscm.NewSCMT(444),
),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(car_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(car_result))
}
if car_result.String() != "333" {
t.Error(car_result)
}
// Test cdr
cdr_result, err := goscm.NewList(
goscm.NewSymbol("cdr"),
goscm.NewList(
goscm.NewSymbol("cons"),
goscm.NewSCMT(555),
goscm.NewSCMT(666),
),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(cdr_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(cdr_result))
}
if cdr_result.String() != "666" {
t.Error(cdr_result)
}
// Test quote
quote_result, err := goscm.NewList(
goscm.NewSymbol("quote"),
goscm.NewList(
goscm.NewSymbol("roar"),
goscm.NewSCMT(1),
goscm.NewSCMT(2),
goscm.NewSymbol("squeak"),
goscm.NewSCMT(3),
goscm.NewSCMT(4),
goscm.NewSCMT(5),
goscm.NewSCMT(6),
goscm.NewSymbol("honk"),
goscm.NewSCMT(7),
goscm.NewSCMT(8),
goscm.NewSCMT(9),
),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(quote_result) != reflect.TypeOf(&goscm.Pair{}) {
t.Error(reflect.TypeOf(quote_result))
}
if quote_result.String() != "(ROAR 1 2 SQUEAK 3 4 5 6 HONK 7 8 9)" {
t.Error(quote_result)
}
// Test begin
// (begin
// (define x 10)
// (* x 3)) => 30
begin_result, err := goscm.NewList(
goscm.NewSymbol("begin"),
goscm.NewList(
goscm.NewSymbol("define"),
goscm.NewSymbol("x"),
goscm.NewSCMT(10),
),
goscm.NewList(
goscm.NewSymbol("*"),
goscm.NewSymbol("x"),
goscm.NewSCMT(3),
),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(begin_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(begin_result))
}
if begin_result.String() != "30" {
t.Error(begin_result)
}
// Test let
// (let ((a 11)
// (b 12))
// (* a b))
// Note: This should clobber the top-level environment's symbol "A"
let_result, err := goscm.NewList(
goscm.NewSymbol("let"),
goscm.NewList(
goscm.NewList(
goscm.NewSymbol("a"),
goscm.NewSCMT(11),
),
goscm.NewList(
goscm.NewSymbol("b"),
goscm.NewSCMT(12),
),
),
goscm.NewList(
goscm.NewSymbol("*"),
goscm.NewSymbol("a"),
goscm.NewSymbol("b"),
),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(let_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(let_result))
}
if let_result.String() != "132" {
t.Error(let_result)
}
// Test lambda
// ((lambda (x) (+ x 2)) 58835) => 58837
lambda_result, err := goscm.NewList(
goscm.NewList(
goscm.NewSymbol("lambda"),
goscm.NewList(
goscm.NewSymbol("x"),
),
goscm.NewList(
goscm.NewSymbol("+"),
goscm.NewSymbol("x"),
goscm.NewSCMT(2),
),
),
goscm.NewSCMT(58835),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(lambda_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(lambda_result))
}
if lambda_result.String() != "58837" {
t.Error(lambda_result)
}
// Test map
// (define square (lambda (x) (* x x)))
// (map square (quote (2 3 4 5 6))) => (4 9 16 25 36)
goscm.NewList(
goscm.NewSymbol("define"),
goscm.NewSymbol("square"),
goscm.NewList(
goscm.NewSymbol("lambda"),
goscm.NewList(
goscm.NewSymbol("x"),
),
goscm.NewList(
goscm.NewSymbol("*"),
goscm.NewSymbol("x"),
goscm.NewSymbol("x"),
),
),
).Eval(env)
map_result, err := goscm.NewList(
goscm.NewSymbol("map"),
goscm.NewSymbol("square"),
goscm.NewList(
goscm.NewSymbol("quote"),
goscm.NewList(
goscm.NewSCMT(2),
goscm.NewSCMT(3),
goscm.NewSCMT(4),
goscm.NewSCMT(5),
goscm.NewSCMT(6),
),
),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(map_result) != reflect.TypeOf(&goscm.Pair{}) {
t.Error(reflect.TypeOf(map_result))
}
if map_result.String() != "(4 9 16 25 36)" {
t.Error(map_result)
}
// Test apply
// (apply + (quote (1 2 3 4 5 6))) => 21
apply_result, err := goscm.NewList(
goscm.NewSymbol("apply"),
goscm.NewSymbol("+"),
goscm.NewList(
goscm.NewSymbol("quote"),
goscm.NewList(
goscm.NewSCMT(1),
goscm.NewSCMT(2),
goscm.NewSCMT(3),
goscm.NewSCMT(4),
goscm.NewSCMT(5),
goscm.NewSCMT(6),
),
),
).Eval(env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(apply_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(apply_result))
}
if apply_result.String() != "21" {
t.Error(apply_result)
}
// Test set!
// (define x 10)
// (set! x 33)
// x => 33
_, err = goscm.EvalStr("(define macamaga 10)", Read, env)
if err != nil {
t.Error(err)
}
_, err = goscm.EvalStr("(set! macamaga 33)", Read, env)
if err != nil {
t.Error(err)
}
set_result, err := goscm.EvalStr("macamaga", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(set_result) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(set_result))
}
if set_result.String() != "33" {
t.Error(set_result)
}
// Test the alternative function definition syntax
// (define (square-plus-cube n m)
// (+ (* n n)
// (* m m m)))
// (square-plus-cube 11 17) => 5034
_, err = goscm.EvalStr(`(define (square-plus-cube n m)
(+ (* n n)
(* m m m)))`, Read, env)
if err != nil {
t.Error(err)
}
altdefine, err := goscm.EvalStr("(square-plus-cube 11 17)", Read, env)
if err != nil {
t.Error(err)
}
if altdefine.String() != "5034" {
t.Error(altdefine)
}
// Test the numerical equality operator for success
// (= 182736 182736) => #t
numeqt, err := goscm.EvalStr("(= 182736 182736 182736)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(numeqt) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(numeqt))
}
if numeqt.String() != "#t" {
t.Error(numeqt)
}
// Test the numerical equality operator for success
// (= 11 12) => #f
numeqf, err := goscm.EvalStr("(= 11 12)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(numeqf) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(numeqf))
}
if numeqf.String() != "#f" {
t.Error(numeqf)
}
// Test if special form for truth side
// (if (= 10 10)
// (+ 2 3)
// (* 20 30)) => 5
ift, err := goscm.EvalStr("(if (= 10 10) (+ 2 3) (* 20 30))", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(ift) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(ift))
}
if ift.String() != "5" {
t.Error(ift)
}
// Test if special form for false side
// (if (= 10 11)
// (+ 2 3)
// (* 20 30)) => 600
iff, err := goscm.EvalStr("(if (= 10 11) (+ 2 3) (* 20 30))", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(iff) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(iff))
}
if iff.String() != "600" {
t.Error(iff)
}
// Check fib works just because we can
// (define (fib n)
// (if (= n 2)
// 1
// (if (= n 1)
// 1
// (+ (fib (- n 1)) (fib (- n 2))))))
// (fib 10) =>
_, err = goscm.EvalStr(`(define (fib n)
(if (= n 2)
1
(if (= n 1)
1
(+ (fib (- n 1)) (fib (- n 2))))))`, Read, env)
if err != nil {
t.Error(err)
}
fib, err := goscm.EvalStr("(fib 10)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(fib) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(fib))
}
if fib.String() != "55" {
t.Error(fib)
}
// Check reading with a dot in the notation
dotcdr, err := goscm.EvalStr("(cdr '(123 . 456))", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(dotcdr) != reflect.TypeOf(&goscm.PlainInt{}) {
t.Error(reflect.TypeOf(dotcdr))
}
if dotcdr.String() != "456" {
t.Error(dotcdr)
}
// Check quote syntax
// (map square '(2 3 4 5 6)) => (4 9 16 25 36
quotesyn, err := goscm.EvalStr("(map square '(2 3 4 5 6))", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(quotesyn) != reflect.TypeOf(&goscm.Pair{}) {
t.Error(reflect.TypeOf(quotesyn))
}
if quotesyn.String() != "(4 9 16 25 36)" {
t.Error(quotesyn)
}
// Check that dotted function arguments work
// (define (pairup a . rest)
// (map (lambda (b) (cons a b)) rest))
// (pairup 3 4 5 6) => ((3 . 4) (3 . 5) (3 . 6))
_, err = goscm.EvalStr(`(define (pairup a . rest)
(map (lambda (b) (cons a b)) rest))`, Read, env)
if err != nil {
t.Error(err)
}
dotlam, err := goscm.EvalStr("(pairup 3 4 5 6)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(dotlam) != reflect.TypeOf(&goscm.Pair{}) {
t.Error(reflect.TypeOf(dotlam))
}
if dotlam.String() != "((3 . 4) (3 . 5) (3 . 6))" {
t.Error(dotlam)
}
// The same as above but with different syntax
// (define pairup2
// (lambda (a . rest)
// (map (lambda (b) (cons a b)) rest)))
// (pairup2 3 4 5 6) => ((3 . 4) (3 . 5) (3 . 6))
_, err = goscm.EvalStr(`(define pairup2
(lambda (a . rest)
(map (lambda (b) (cons a b)) rest)))`, Read, env)
if err != nil {
t.Error(err)
}
dotlam2, err := goscm.EvalStr("(pairup2 3 4 5 6)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(dotlam2) != reflect.TypeOf(&goscm.Pair{}) {
t.Error(reflect.TypeOf(dotlam2))
}
if dotlam2.String() != "((3 . 4) (3 . 5) (3 . 6))" {
t.Error(dotlam2)
}
// 'not' should return #t when passed #f
nota, err := goscm.EvalStr("(not #f)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(nota) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(nota))
}
if nota.String() != "#t" {
t.Error(nota)
}
// 'not' should return #f when passed an integer or anything but #t
notb, err := goscm.EvalStr("(map not '(2364 #f #t 4))", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(notb) != reflect.TypeOf(&goscm.Pair{}) {
t.Error(reflect.TypeOf(notb))
}
if notb.String() != "(#f #t #f #f)" {
t.Error(notb)
}
// Test for < of a long list in which it is true
ltt, err := goscm.EvalStr(`(and (< 2 100 101 200 203 1000)
(< 3 5)
(< 8 9 11 12))`, Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(ltt) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(ltt))
}
if ltt.String() != "#t" {
t.Error(ltt)
}
// Test for < of a long list in which it is false
ltf, err := goscm.EvalStr(`(or (< 2 100 100 1 203 1000)
(< 4 3)
(< 99 100 99 101))`, Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(ltf) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(ltf))
}
if ltf.String() != "#f" {
t.Error(ltf)
}
// Test for > of a long list in which it is true
gtt, err := goscm.EvalStr(`(and (> 1000 202 201 200 50 5 1)
(> 9 8 7 6 5 4 3 2 1)
(> 3 2))`, Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(gtt) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(gtt))
}
if gtt.String() != "#t" {
t.Error(gtt)
}
// Test for > of a long list in which it is false
gtf, err := goscm.EvalStr(`(or (> 10000 5000 5000 20 30 0 44)
(> 10 11)
(> 100 99 100 99))`, Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(gtf) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(gtf))
}
if gtf.String() != "#f" {
t.Error(gtf)
}
// Test for 'and' when it should succeed
andt, err := goscm.EvalStr("(and #t #t #t #t #t #t #t #t #t #t)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(andt) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(andt))
}
if andt.String() != "#t" {
t.Error(andt)
}
// Test for 'and' when it should fail
// TODO: Ensure that eval only happens if previous cases are true
andf, err := goscm.EvalStr("(and #t #t #t #t #t #t #t #f #t #t)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(andf) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(andf))
}
if andf.String() != "#f" {
t.Error(andf)
}
// Test for 'or' when it should succeed
// TODO test that eval is only happening when it should
ort, err := goscm.EvalStr("(or #f #f #f #f #f #f #t #f #f)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(ort) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(ort))
}
if ort.String() != "#t" {
t.Error(ort)
}
// Test for 'or' when it should fail
// TODO test that eval is only happening when it should
orf, err := goscm.EvalStr("(or #f #f #f #f #f #f #f #f #f)", Read, env)
if err != nil {
t.Error(err)
}
if reflect.TypeOf(orf) != reflect.TypeOf(&goscm.Boolean{}) {
t.Error(reflect.TypeOf(orf))
}
if orf.String() != "#f" {
t.Error(orf)
}
// Test for '>=' when it should pass
get, err := goscm.EvalStr(`(and (>= 10 10 10 10 9 9 9 9 8 8 7 7)
(>= 11 11)
(>= 9 8))`, Read, env)
if err != nil {
t.Error(err)
}
if get.String() != "#t" {
t.Error(get)
}
// Test for '>=' when it should fail
gef, err := goscm.EvalStr(`(or (>= 10 10 10 10 9 9 9 9 10 8 7)
(>= 11 12))`, Read, env)
if err != nil {
t.Error(err)
}
if gef.String() != "#f" {
t.Error(gef)
}
// Test for '<=' when it should pass
let, err := goscm.EvalStr(`(and (<= 10 10 11 11 11 2001)
(<= 11 12))`, Read, env)
if err != nil {
t.Error(err)
}
if let.String() != "#t" {
t.Error(let)
}
// Test for '<=' when it should fail
lef, err := goscm.EvalStr(`(or (<= 10 10 10 10 9 10 10 11 14)
(<= 11 10))`, Read, env)
if err != nil {
t.Error(err)
}
if lef.String() != "#f" {
t.Error(lef)
}
// Test for 'reverse'
rev, err := goscm.EvalStr(`(reverse '(1 2 3 (+ 88 22) 4 6))`, Read, env)
if err != nil {
t.Error(err)
}
if rev.String() != "(6 4 (+ 88 22) 3 2 1)" {
t.Error(rev)
}
// Test for 'list'
list_func, err := goscm.EvalStr(`(list 2 3 4 'a 3 5 67)`, Read, env)
if err != nil {
t.Error(err)
}
if list_func.String() != "(2 3 4 A 3 5 67)" {
t.Error(list_func)
}
// Test for recursive function application
_, err = goscm.EvalStr("(define (my-square x) (* x x)))", Read, env)
if err != nil {
t.Error(err)
}
my_square, err := goscm.EvalStr("(square (square 10))", Read, env)
if err != nil {
t.Error(err)
}
if my_square.String() != "10000" {
t.Error(my_square)
}
// A basic test for cond
// TODO: Check what happens on complete fallthrough and that only the
// condition which is selected it evaluated
cond, err := goscm.EvalStr(`(cond (#f (+ 2 4 5))
(#f (* 10 20))
(#t (/ 110 2)))`, Read, env)
if err != nil {
t.Error(err)
}
if cond.String() != "55" {
t.Error(cond)
}
}