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Phil: please don't take this personally :) I am writing this only
because I have seen so many people following this path lately, and
getting frustrated.

Phil Bewig escribe:

>  As an exercise in learning to program in lua, and because I
> think it will be a useful library to have, I am writing a
> library to manipulate linked lists.

In other words, you seek to learn how to program in Lua by writing
a program in C, a language in which you are presumably already
fluent, in order to create a datatype not present in Lua so that
you could program in Lua as though it were, perhaps, Lisp, a
language in which you are also presumably fluent.

This does not strike me as the best way to learn Lua. In fact,
this sort of approach is likely to end up with your fighting
with Lua and ultimately abandoning it for some language you feel
more comfortable with. It rather reminds me of the sadly typical
marriage in which both partners, although they have fallen in love
with each other, immediately set out to change the other into
someone else, someone who they had not fallen in love with. This
can only end in tears.

If you want to learn a new language, you should at least spend a
little time getting to understand how it fits together on its own
terms, not as though it were some other language. Lua does not
have linked lists, but it is still a useful and reasonably fast
language. Why? Because other programming styles and datatypes
fill that particular gap. Not, perhaps, perfectly, but well enough.
At the same time, Lua provides other facilities not common in
scripting languages, which simplify solving other types of problems.

Despite the kitchen-sinkism of Perl, programming languages are not
just lists of features. A well-designed programming language is a
coherent whole whose paradigms complement each other; things are
present because they fit and other things are absent because they

On a more pragmatic level, if you continue with this project, I think
you will end up getting very frustrated, because what you seek to do
probably cannot be done, and certainly cannot be done easily.

Like most scripting environments, Lua is pretty well a sealed unit.
Internal datatypes are internal, and cannot easily be extracted and
replaced later. (This is particularly the case for languages built
around garbage collection, for reasons which should be obvious. How,
for example, would you anticipate freeing a cons node?)

This is not to say that Lua is unwilling to share. Its C interface
is very well defined and quite easy to use. You just have to use it
on its own terms.