func Get(env *Environment, sym *types.Symbol) (types.Type, error) {
for e := env; e != nil; e = e.parent {
for v := e.env; v != nil; {
testSym, err := types.Caar(v)
if err != nil {
return nil, &envError{fmt.Sprintf("Checking for %s", sym.Value), err}
}
if types.Eqv(sym, testSym) {
if r, err := types.Cdar(v); err != nil {
return nil, &envError{fmt.Sprintf("Checking for %s", sym.Value), err}
} else {
return r, nil
}
}
nextV, _ := types.Cdr(v)
var ok bool
v, ok = nextV.(*types.Pair)
if !ok {
return nil, &envError{m: "Corrupt environment!!!"}
}
}
}
return nil, &envError{m: fmt.Sprintf("Unknown variable: %s", sym.Value)}
}
func cdr(env interface{}, args t.Type) (t.Type, error) {
return t.Cdar(args)
}