Philipp Stephani <p.stephani2@gmail.com> schrieb am Mo., 9. Mai 2016 um
18:39 Uhr:

>
> emacs_env::make_function lacks the following features supported by
> `defun':
>
> 1. Functions with both optional and rest arguments.
> 2. Specification of parameter names.
> 3. Integration with `help-function-arglist'.
> 4. Specification of interactive forms.
> 5. Specification of declare forms.
> 6. Docstrings containing null or non-Unicode characters.
>
> (6) is probably rather unimportant.  (5) is probably not implementable
> (would require wrapping `defun', not `lambda').  (1)–(4) are more severe
> and quite limit the usefulness of make_function right now; for a
> truly generic `defun'-like construct one currently has to eval a `defun'
> form wrapping another function.
>
> To solve (1)–(3), I'd propose replacing the "arity" arguments with a
> true arglist specification.  This could either be at the C level, e.g.
>
>     ptrdiff_t num_mandatory_args, char** mandatory_arg_names,
>     ptrdiff_t num_optional_args, char** optional_arg_names,
>     char* rest_arg_name
>
> or by requiring to pass a Lisp argument list.
>

I've attached a patch for fixing (1)-(4) and (6).