-- This file:
--   http://angg.twu.net/LUA/LpegRex1.lua.html
--   http://angg.twu.net/LUA/LpegRex1.lua
--           (find-angg "LUA/LpegRex1.lua")
-- Author: Eduardo Ochs <eduardoochs@gmail.com>
--
-- Tests for lpegrex.
-- See: (find-es "lpeg" "lpegrex")
--      (find-lpegrexpage)
--      (find-lpegrextext)
--      (find-lpegrexpage 6 "__options =")
--      (find-lpegrextext 6 "__options =")
--
-- (defun a () (interactive) (find-angg "LUA/Arith4.lua"))
-- (defun l () (interactive) (find-angg "LUA/LpegRex1.lua"))
--
-- «.rectfromast»	(to "rectfromast")


Path.prepend("cpath", "~/usrc/lpeglabel/?.so")
Path.prepend("path",  "~/usrc/lpegrex/?.lua")
lpegrex = require "lpegrex"

Grammar = [==[
  top           <-- plusexpr
  plusexpr      <-| timesexpr ({"+"} timesexpr)*
  timesexpr     <-| norp      ({"*"} norp)*
  norp          <-| num     / ("(" plusexpr ")") 
  num           <-- {%d}
]==]

patt = lpegrex.compile(Grammar)
bigstr = "(1+2)*3"
ast, errlabel, errpos = patt:match(bigstr)
-- PPPV(ast, errlabel, errpos)

__options = {}

t0 = function (str)
    local gram,subj = str:match("^(.-)::%s*(.*)$")
    -- local patt = lpegrex.compile(gram)
    local patt = lpegrex.compile(gram, {__options = __options})
    ast,errlabel,errpos = patt:match(subj)
    PP(ast)
  end

simplify = function (o)
    if type(o) ~= "table" then return o end
    if #o == 1 then return simplify(o[1]) end
    return map(simplify, o)
  end

-- «rectfromast»  (to ".rectfromast")
-- (find-angg "LUA/Rect.lua" "Rect")
-- (find-angg "LUA/Rect.lua" "SynTree")
--
rectfromast = function (o)
    if type(o) == "number" then return Rect.from(o) end
    if type(o) == "string" then return Rect.from(o) end
    if type(o) == "table" then
      local out = rectfromast(o[#o]):syn1()
      for i=#o-2,1,-2 do
        local lowerleft = rectfromast(o[i])
        local left = lowerleft:syn1(o[i+1])
        local left_ = left:pad0(1, left:width()+2, "_")
        out = left_ .. out
      end
      return out
    end
    PP("rectfromast can't handle this", o)
  end

--[==[
* (eepitch-lua52)
* (eepitch-kill)
* (eepitch-lua52)
dofile "LpegRex1.lua"

= rectfromast(42)
= rectfromast(42):syn1()
= Rect.from(42):syn1()
= rectfromast({42})
= rectfromast({2, "+", 3, "-", 4})
= rectfromast({2, "+", {5, "*", 6}, "-", 4})
= a
= a:syn1()


--]==]



--[==[
* (eepitch-lua52)
* (eepitch-kill)
* (eepitch-lua52)
dofile "LpegRex1.lua"
t0 [=[ top <-- {%d}   :: 42 ]=]
t0 [=[ top <-| {%d}   :: 42 ]=]
t0 [=[ top <== {%d}   :: 42 ]=]
t0 [=[ top : foo <== {%d}*   :: 42 ]=]

t0 [=[ top <== num*
       num <-- {%d}
       :: 42
   ]=]
t0 [=[ top <-| num*
       num <== {%d}
       :: 42
   ]=]
t0 [=[ top : nums <== num*
       num <== {%d}
       :: 42
   ]=]

t0 [=[ top     <-- addexpr
       norp    <-- num / "(" addexpr ")"
       addexpr <== mulexpr ({"+"} mulexpr)*
       mulexpr <== norp    ({"*"} norp)*
       num     <== {%d+}
       :: (1+2*3*4+5)*6+7
   ]=]
PPPV(ast)

asts = simplify(ast)
astr = rectfromast(asts)
PPP(asts)
= astr

-- Ugly:
= rectfromast(ast)

--]==]






--[==[
* (eepitch-lua52)
* (eepitch-kill)
* (eepitch-lua52)
dofile "LpegRex1.lua"
-- (find-lpegrexpage 6 "__options =")
-- (find-lpegrextext 6 "__options =")
__options = {
  tag = function(tag, node)
      print('new node', tag)
      node.tag = tag
      return node
    end
}
t0 [=[ top : nums <== num*
       num <== {%d}
       :: 42
   ]=]

--]==]





-- Local Variables:
-- coding:  utf-8-unix
-- End: