# This file:
#   https://github.com/edrx/edrxrepl/
#       http://angg.twu.net/edrxrepl/README.org.html
#       http://angg.twu.net/edrxrepl/README.org
#               (find-angg "edrxrepl/README.org")
#               (find-angg "edrxrepl/")
# Author: Eduardo Ochs <eduardoochs@gmail.com>
# 
# Some eev-isms:
# (defun c  () (interactive) (eek "C-c C-e h h"))
# (defun l  () (interactive) (find-angg "edrxrepl/edrxrepl.lua"))
# (defun o  () (interactive) (find-angg "edrxrepl/README.org"))
# (defun v  () (interactive) (brg     "~/edrxrepl/README.html"))
# (defun cv () (interactive) (c) (v))
# (defun er () (interactive) (find-es "lua5" "Repl-emacs-lua"))
# (defun e  () (interactive) (find-es "lua5"))
#   (find-es "lua5" "Repl")
#   (find-es "magit" "edrxrepl")
# 
# (find-mygitrepo-links "edrxrepl")
# (find-orgnode "Table of Contents")
#+OPTIONS: toc:nil num:nil

* Introduction
This is a simple [[https://en.wikipedia.org/wiki/Read%E2%80%93eval%E2%80%93print_loop][REPL]] for Lua.

# https://github.com/edrx/edrxrepl
# (find-eepitch-intro)
# (brg "~/edrxrepl/README.html")

I wrote it because I was tired of not understanding the innards of Rob
Hoelz's [[https://github.com/hoelzro/lua-repl/][lua-repl]]. As I use [[http://angg.twu.net/eev-intros/find-eepitch-intro.html][eepitch]] I need very few features from my
REPLs -- for example, I don't need history or completion.

The [[http://angg.twu.net/edrxrepl/edrxrepl.lua.html][code]] of this REPL is made of:

- a few functions copied from my [[http://angg.twu.net/LUA/lua50init.lua.html][init file]],

- my implementation on OO in 5 lines (a commented version of it is
  [[http://angg.twu.net/dednat6/dednat6/eoo.lua.html][here]]),

- the class [[http://angg.twu.net/edrxrepl/edrxrepl.lua.html#MyXpcall][MyXpcall]], that is a hacker-friendly wrapper around Lua's
  [[https://www.lua.org/manual/5.1/manual.html#pdf-xpcall][xpcall]]; I wrote it because I needed better error handling in [[http://angg.twu.net/dednat6/tug-slides.pdf#page=9][Dednat6]]
  -- I need several different error handlers, each with its own
  [[https://www.lua.org/manual/5.1/manual.html#pdf-debug.traceback][traceback function]].

- the class [[http://angg.twu.net/edrxrepl/edrxrepl.lua.html#Repl][Repl]], that uses MyXpcall to run the user code. Once
  MyXpcall was working the class Repl was trivial to write.

The code is full of [[http://angg.twu.net/#eev][eev]]-isms, but they are all in comments and can be
ignored. Some of the multi-line comments are [[http://angg.twu.net/eev-intros/find-eepitch-intro.html#3][test blocks]].

Here's an example of how to use it from Lua. Note that the REPL uses
~>>>~ and ~...~ for its prompts.

#+BEGIN_SRC
cd ~/edrxrepl/
/home/edrx/edrxrepl(edrx:sc)# lua5.3
Lua 5.3.3  Copyright (C) 1994-2016 Lua.org, PUC-Rio
> dofile "edrxrepl.lua"
> REPL = EdrxRepl.new(); REPL:repl()
>>> print(
...   1+2
... )
3
>>> = 1+2
3
>>> = 1, 2, 3
1	2	3
>>> = nil, 22
nil	22
>>> REPL.stop = 1
> os.exit()
/home/edrx/edrxrepl(edrx:sc)# 
#+END_SRC

And here is an example of how to use it from LuaLaTeX (without git!):

#+BEGIN_SRC
rm -Rfv /tmp/edrxrepl
mkdir   /tmp/edrxrepl/
cd      /tmp/edrxrepl/
wget http://angg.twu.net/edrxrepl/edrxrepl.lua
wget http://angg.twu.net/edrxrepl/edrxrepltest.tex
lualatex edrxrepltest.tex
#+END_SRC

The body of [[http://angg.twu.net/edrxrepl/edrxrepltest.tex.html][edrxrepltest.tex]] is just this:

#+BEGIN_SRC latex
\documentclass{article}
\begin{document}

\directlua{dofile "edrxrepl.lua"}
\directlua{print(); print(); print("Run REPL.stop = 1 to leave the REPL.")}
\directlua{REPL = EdrxRepl.new(); REPL:repl()}

\end{document}
#+END_SRC

I am also using this in emacs-lua, that at this moment is just a messy
prototype.



#+begin_comment
* (eepitch-shell)
* (eepitch-kill)
* (eepitch-shell)
cd ~/edrxrepl/
laf
rm -v *~
rm -v *.html

# (find-fline   "~/edrxrepl/")
# (magit-status "~/edrxrepl/")
# (find-gitk    "~/edrxrepl/")
#
#   (s)tage all changes
#   (c)ommit -> (c)reate
#   (P)ush -> (p)ushremote
#   https://github.com/edrx/edrxrepl
#
#+end_comment

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# coding:               utf-8-unix
# modes:                (org-mode fundamental-mode)
# org-html-postamble:   nil
# End: