func Env() *goscm.Environ {
env := goscm.NewEnv(nil)
env.Add(goscm.NewSymbol("*"), goscm.NewForeign(scm_multiply))
env.Add(goscm.NewSymbol("+"), goscm.NewForeign(scm_add))
env.Add(goscm.NewSymbol("-"), goscm.NewForeign(scm_subtract))
env.Add(goscm.NewSymbol("/"), goscm.NewForeign(scm_divide))
env.Add(goscm.NewSymbol("<"), goscm.NewForeign(scm_lt))
env.Add(goscm.NewSymbol("<="), goscm.NewForeign(scm_le))
env.Add(goscm.NewSymbol("="), goscm.NewForeign(scm_numeq))
env.Add(goscm.NewSymbol(">"), goscm.NewForeign(scm_gt))
env.Add(goscm.NewSymbol(">="), goscm.NewForeign(scm_ge))
env.Add(goscm.NewSymbol("apply"), goscm.NewForeign(scm_apply))
env.Add(goscm.NewSymbol("car"), goscm.NewForeign(scm_car))
env.Add(goscm.NewSymbol("cdr"), goscm.NewForeign(scm_cdr))
env.Add(goscm.NewSymbol("cons"), goscm.NewForeign(scm_cons))
env.Add(goscm.NewSymbol("list"), goscm.NewForeign(scm_list))
env.Add(goscm.NewSymbol("map"), goscm.NewForeign(scm_map))
env.Add(goscm.NewSymbol("not"), goscm.NewForeign(scm_not))
env.Add(goscm.NewSymbol("reverse"), goscm.NewForeign(scm_reverse))
env.Add(goscm.NewSymbol("and"), goscm.NewSpecial(scm_and))
env.Add(goscm.NewSymbol("begin"), goscm.NewSpecial(scm_begin))
env.Add(goscm.NewSymbol("define"), goscm.NewSpecial(scm_define))
env.Add(goscm.NewSymbol("lambda"), goscm.NewSpecial(scm_lambda))
env.Add(goscm.NewSymbol("let"), goscm.NewSpecial(scm_let))
env.Add(goscm.NewSymbol("or"), goscm.NewSpecial(scm_or))
env.Add(goscm.NewSymbol("quote"), goscm.NewSpecial(scm_quote))
env.Add(goscm.NewSymbol("set!"), goscm.NewSpecial(scm_set_bang))
env.Add(goscm.NewSymbol("if"), goscm.NewSpecialTCO(scm_if))
env.Add(goscm.NewSymbol("cond"), goscm.NewSpecialTCO(scm_cond))
return env
}
func scm_let(args *goscm.Pair, env *goscm.Environ) (goscm.SCMT, error) {
body := args.Cdr.(*goscm.Pair)
newenv := goscm.NewEnv(env)
for vars := args.Car.(*goscm.Pair); vars != goscm.SCM_Nil; vars = vars.Cdr.(*goscm.Pair) {
symb := vars.Car.(*goscm.Pair).Car.(*goscm.Symbol)
val, err := vars.Car.(*goscm.Pair).Cdr.(*goscm.Pair).Car.Eval(env)
if err != nil {
return goscm.SCM_Nil, err
}
newenv.Add(symb, val)
}
return scm_begin(body, newenv)
}