nomsu/parser.lua

local lpeg = require('lpeg')
local re = require('re')
lpeg.setmaxstack(20000)
local P, R, S, C, Cmt, Carg
P, R, S, C, Cmt, Carg = lpeg.P, lpeg.R, lpeg.S, lpeg.C, lpeg.Cmt, lpeg.Carg
local match, sub
do
  local _obj_0 = string
  match, sub = _obj_0.match, _obj_0.sub
end
local insert, remove
do
  local _obj_0 = table
  insert, remove = _obj_0.insert, _obj_0.remove
end
local files = require('files')
local NomsuCode, LuaCode, Source
do
  local _obj_0 = require("code_obj")
  NomsuCode, LuaCode, Source = _obj_0.NomsuCode, _obj_0.LuaCode, _obj_0.Source
end
local AST = require("syntax_tree")
local NOMSU_DEFS
do
  local _with_0 = { }
  _with_0.nl = P("\r") ^ -1 * P("\n")
  _with_0.ws = S(" \t")
  _with_0.tonumber = tonumber
  _with_0.table = function()
    return { }
  end
  _with_0.unpack = unpack or table.unpack
  local string_escapes = {
    n = "\n",
    t = "\t",
    b = "\b",
    a = "\a",
    v = "\v",
    f = "\f",
    r = "\r"
  }
  local digit, hex = R('09'), R('09', 'af', 'AF')
  _with_0.escaped_char = (P("\\") * S("xX") * C(hex * hex)) / function(self)
    return string.char(tonumber(self, 16))
  end
  _with_0.escaped_char = _with_0.escaped_char + ((P("\\") * C(digit * (digit ^ -2))) / function(self)
    return string.char(tonumber(self))
  end)
  _with_0.escaped_char = _with_0.escaped_char + ((P("\\") * C(S("ntbavfr"))) / string_escapes)
  _with_0.operator_char = S("'`~!@$^&*+=|<>?/-")
  _with_0.utf8_char = (R("\194\223") * R("\128\191") + R("\224\239") * R("\128\191") * R("\128\191") + R("\240\244") * R("\128\191") * R("\128\191") * R("\128\191"))
  _with_0.ident_char = R("az", "AZ", "09") + P("_") + _with_0.utf8_char
  _with_0.userdata = Carg(1)
  _with_0.add_comment = function(src, end_pos, start_pos, comment, userdata)
    userdata.comments[start_pos] = comment
    return true
  end
  _with_0.error = function(src, end_pos, start_pos, err_msg, userdata)
    local seen_errors = userdata.errors
    if seen_errors[start_pos] then
      return true
    end
    local num_errors = 0
    for _ in pairs(seen_errors) do
      num_errors = num_errors + 1
    end
    if num_errors >= 10 then
      seen_errors[start_pos + 1] = colored.bright(colored.yellow(colored.onred("Too many errors, canceling parsing...")))
      return #src + 1
    end
    local err_pos = start_pos
    local line_no = files.get_line_number(src, err_pos)
    local prev_line = line_no == 1 and nil or files.get_line(src, line_no - 1)
    local err_line = files.get_line(src, line_no)
    local next_line = files.get_line(src, line_no + 1)
    local i = err_pos - files.get_line_starts(src)[line_no]
    local j = i + (end_pos - start_pos)
    local pointer = ("-"):rep(i) .. "^"
    err_msg = colored.bright(colored.yellow(colored.onred((err_msg or "Parse error") .. " at " .. tostring(userdata.source.filename) .. ":" .. tostring(line_no) .. ":")))
    if prev_line then
      err_msg = err_msg .. ("\n" .. colored.dim(prev_line))
    end
    if err_line then
      err_line = colored.white(err_line:sub(1, i)) .. colored.bright(colored.red(err_line:sub(i + 1, j + 1))) .. colored.dim(err_line:sub(j + 2, -1))
      err_msg = err_msg .. "\n" .. tostring(err_line) .. "\n" .. tostring(colored.red(pointer))
    end
    if next_line then
      err_msg = err_msg .. ("\n" .. colored.dim(next_line))
    end
    seen_errors[start_pos] = err_msg
    return true
  end
  NOMSU_DEFS = _with_0
end
setmetatable(NOMSU_DEFS, {
  __index = function(self, key)
    local make_node
    make_node = function(start, value, stop, userdata)
      if userdata.source then
        do
          local _with_0 = userdata.source
          value.source = Source(_with_0.filename, _with_0.start + start - 1, _with_0.start + stop - 1)
        end
      end
      setmetatable(value, AST[key])
      if value.__init then
        value:__init()
      end
      return value
    end
    self[key] = make_node
    return make_node
  end
})
local Parser = {
  version = 4,
  patterns = { }
}
Parser.is_operator = function(s)
  return not not (NOMSU_DEFS.operator_char ^ 1 * -1):match(s)
end
Parser.is_identifier = function(s)
  return not not (NOMSU_DEFS.ident_char ^ 1 * -1):match(s)
end
local inline_escaper = re.compile("{~ (%utf8_char / ('\"' -> '\\\"') / ('\n' -> '\\n') / ('\t' -> '\\t') / ('\b' -> '\\b') / ('\a' -> '\\a') / ('\v' -> '\\v') / ('\f' -> '\\f') / ('\r' -> '\\r') / ('\\' -> '\\\\') / ([^ -~] -> escape) / .)* ~}", {
  utf8_char = NOMSU_DEFS.utf8_char,
  escape = (function(self)
    return ("\\%03d"):format(self:byte())
  end)
})
Parser.inline_escape = function(s)
  return inline_escaper:match(s)
end
local escaper = re.compile("{~ (%utf8_char / ('\\' -> '\\\\') / [\n\r\t -~] / (. -> escape))* ~}", {
  utf8_char = NOMSU_DEFS.utf8_char,
  escape = (function(self)
    return ("\\%03d"):format(self:byte())
  end)
})
Parser.escape = function(s)
  return escaper:match(s)
end
return Parser