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Warning: this is an htmlized version!
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-- This file: EdrxRepl.lua - a REPL for Lua.
-- https://github.com/edrx/emacs-lua/
-- http://angg.twu.net/emacs-lua/EdrxRepl.lua.html
-- http://angg.twu.net/emacs-lua/EdrxRepl.lua
-- (find-angg "emacs-lua/EdrxRepl.lua")
--
-- In the HTML version the sexp hyperlinks work.
-- See: (find-eev-quick-intro "3. Elisp hyperlinks")
-- (find-eepitch-intro "3. Test blocks")
--
-- Author: Eduardo Ochs <eduardoochs@gmail.com>
-- Version: 20210918
-- License: GPL3 at this moment.
-- If you need another license, get in touch!
--
-- Some eev-isms:
-- (defun o () (interactive) (find-angg "emacs-lua/README.org"))
-- (defun r () (interactive) (find-angg "emacs-lua/EdrxRepl.lua"))
-- (defun x () (interactive) (find-angg "emacs-lua/EdrxPcall.lua"))
-- This file is being rewritten.
-- The class EdrxRepl uses
-- the class EdrxPcall,
-- that is defined here:
require "EdrxPcall" -- (find-angg "emacs-lua/EdrxPcall.lua")
-- «.EdrxRepl» (to "EdrxRepl")
-- «.EdrxRepl-emacs» (to "EdrxRepl-emacs")
-- «.EdrxRepl-tests» (to "EdrxRepl-tests")
-- «.dbg-tests» (to "dbg-tests")
-- ____ _
-- | _ \ ___ _ __ | |
-- | |_) / _ \ '_ \| |
-- | _ < __/ |_) | |
-- |_| \_\___| .__/|_|
-- |_|
--
-- «EdrxRepl» (to ".EdrxRepl")
-- Also in: (find-angg "LUA/lua50init.lua" "Repl")
-- A simple REPL for Lua that handles errors well enough.
-- It uses EdrxPcall to run code.
-- Usage:
--
-- REPL = EdrxRepl:new(); REPL:repl()
--
-- To exit the REPL set REPL.stop to true.
--
-- NOTE ON '='s: The EdrxRepl class implements a trick that is found in
-- the REPLs of Lua5.1 and Lua5.2 but was dropped from Lua5.3 onwards.
-- It is explained in the manpages for lua5.1 and lua5.2 as:
--
-- If a line starts with '=', then lua displays the values of all
-- the expressions in the remainder of the line. The expressions
-- must be separated by commas.
--
-- In Lua5.3 they changed that to this (also copied from the manpage):
--
-- If the line contains an expression or list of expressions, then
-- the line is evaluated and the results are printed.
--
-- See for example this thread:
-- http://lua-users.org/lists/lua-l/2020-10/msg00209.html
EdrxRepl = Class {
type = "EdrxRepl",
new = function () return EdrxRepl({}) end,
__index = {
bigstr = function (r) return table.concat(r.lines, "\n") end,
code = function (r) return r:bigstr():gsub("^=", "return ") end,
--
-- incompletep = function (r) return r:incompletep0(r:code()) end,
-- incompletep0 = function (r, bigstr)
-- local f, err = loadstring(bigstr)
-- return (f == nil) and r:incompleteerrp(err)
-- end,
--
read00 = function (r, prompt) io.write(prompt); return io.read() end,
read0 = function (r, prompt) table.insert(r.lines, r:read00(prompt)) end,
read1 = function (r) return r:read0 ">>> " end,
read2 = function (r) return r:read0 "... " end,
read = function (r)
r.lines = {}
r:read1()
while r:trapincomplete() do r:read2() end
return r
end,
--
incompleteerrp = function (r, err)
return err:find(" near '?<eof>'?$")
end,
trapincomplete = function (r)
r.f, r.err = loadstring(r:code())
return (r.err and r:incompleteerrp(r.err)) and "[incomplete]"
end,
trapcomperror = function (r)
r.f, r.err = loadstring(r:code())
return r.err and "[comp error]"
end,
trapexecerror = function (r)
r.xpc = EdrxPcall.new():call(r.f)
if not r.xpc:success() then
r.err = r.xpc.err_msg
r.tb = r.xpc:tbshorter()
return "[exec error]"
end
end,
printcomperror = function (r) print(r.err) end,
printexecerror = function (r) print(r.err) end,
readevalprint = function (r)
r:read()
if r:trapcomperror() then return r:printcomperror() end
if r:trapexecerror() then return r:printexecerror() end
if r:bigstr():match("^=")
then print(r.xpc:outsuccess())
end
end,
--
-- The standard interface:
repl = function (r) while not r.stop do r:readevalprint() end end,
--
-- «EdrxRepl-emacs» (to ".EdrxRepl-emacs")
-- The emacs interface:
erepltest = function (r)
while not r.stop do
print(r:esend(r:read00(r:eprompt())))
end
end,
--
e0 = function (r) r.lines = {}; return r end, -- clear .lines
eprompt = function (r)
r.lines = r.lines or {}
if #r.lines == 0 then return ">>> " else return "... " end
end,
etrapexecerror = function (r)
r.xpc = EdrxPcall.new():prcall(r.f)
if not r.xpc:success() then
r.err = r.xpc.err_msg
r.tb = r.xpc:tbshorter()
return "[exec error]"
end
end,
esend = function (r, line)
table.insert(r.lines, line)
if r: trapincomplete() then return r:eretincomplete() end
if r: trapcomperror() then return r:e0():eretcomperror() end
if r:etrapexecerror() then return r:e0():eretexecerror() end
if r:bigstr():match("^=")
then return r:e0():eretsuccessprint()
else return r:e0():eretsuccessnonprint()
end
end,
eretincomplete = function (r) return "(incomplete)" end,
eretcomperror = function (r) return "(comp error)", r.err end,
eretexecerror = function (r) return "(exec error)", r.xpc:prout(nil, "\n") end,
eretsuccessprint = function (r) return "(success: =)", r.xpc:prout("=", "\n") end,
eretsuccessnonprint = function (r) return "(success)", r.xpc:prout() end,
},
}
-- «EdrxRepl-tests» (to ".EdrxRepl-tests")
-- (find-elisp-intro "5. Variables" "If you execute lines 1, 3, and 4")
-- (find-angg "LUA/lua50init.lua")
--[[
* (eepitch-shell)
* (eepitch-kill)
* (eepitch-shell)
export LUA_INIT=""
export LUA_INIT=@$HOME/LUA/lua50init.lua
lua5.1
lua5.2
lua5.3
lua5.4
PP()
* (eepitch-lua51)
* (eepitch-kill)
* (eepitch-lua51)
dofile "EdrxRepl.lua"
REPL = EdrxRepl.new()
-- REPL:repl()
REPL:repl()
print(
1+2
)
= 1+2
= 1, 2, 3
= 20, 30, nil, 40, nil
REPL.stop = 1
* (eepitch-lua51)
* (eepitch-kill)
* (eepitch-lua51)
dofile "EdrxRepl.lua"
REPL = EdrxRepl.new()
REPL:erepltest()
print(
1+2
)
= 1+2
= 1, 2, 3
= 20, 30, nil, 40, nil
a = 22
a = a + 33
a = a +
200
= a
= a +
2 +
3
= a +
2 +
nil
REPL.stop = 1
REPL.stop = 1
* (eepitch-lua51)
* (eepitch-kill)
* (eepitch-lua51)
dofile "EdrxRepl.lua"
EdrxPcall.__index.tb_e = 10
EdrxPcall.__index.tb_e = 5
EdrxPcall.__index.tb_e = 6
REPL = EdrxRepl.new()
REPL:erepltest()
= a + 2 + nil
--]]