func define(s *scheme.Scope, args []scheme.Sexpr) (scheme.Sexpr, error) {
if len(args) != 2 {
return nil, scheme.ProcError("define requires exactly 2 arguments")
}
idSym, ok := args[0].(*scheme.Symbol)
if !ok {
return nil, scheme.ProcError("invalid argument to define")
}
val, err := eval.Eval(s, args[1])
if err != nil {
return nil, err
}
s.DefineHigh(idSym, val)
return scheme.Nil, nil
}
