[pdftex] Experiment with a new TeX primitive

[Nagy Bence]

I found it: the solution is the usage of str_toks(), but
this function points to the last char of the returned string. The
back_list(temp_head) returns with an invalid node (HZ) error message,
back_list(link(temp_head)) makes a 50 pages long document from
the words of the primitives.

> procedure experiment;
> var q: pointer;
> begin
>     call_func(scan_toks(false, true));
>     q:=str_toks(experiment(def_ref));
>     back_list(temp_head);
>     delete_token_ref(def_ref);
> end

What is wrong?

Greetings,

Bence