nomsu/nomsu_compiler.lua

local lpeg = require('lpeg')
local R, P, S
R, P, S = lpeg.R, lpeg.P, lpeg.S
local re = require('re')
local utils = require('utils')
local Files = require('files')
local stringify, equivalent
stringify, equivalent = utils.stringify, utils.equivalent
local List, Dict, Text
do
  local _obj_0 = require('containers')
  List, Dict, Text = _obj_0.List, _obj_0.Dict, _obj_0.Text
end
colors = require('consolecolors')
colored = setmetatable({ }, {
  __index = function(_, color)
    return (function(msg)
      return colors[color] .. tostring(msg or '') .. colors.reset
    end)
  end
})
local insert, remove, concat
do
  local _obj_0 = table
  insert, remove, concat = _obj_0.insert, _obj_0.remove, _obj_0.concat
end
local unpack = unpack or table.unpack
local match, sub, gsub, format, byte, find
do
  local _obj_0 = string
  match, sub, gsub, format, byte, find = _obj_0.match, _obj_0.sub, _obj_0.gsub, _obj_0.format, _obj_0.byte, _obj_0.find
end
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 SyntaxTree = require("syntax_tree")
local make_parser = require("parser")
local pretty_error = require("pretty_errors")
SOURCE_MAP = { }
table.map = function(t, fn)
  return setmetatable((function()
    local _accum_0 = { }
    local _len_0 = 1
    for _, v in ipairs(t) do
      _accum_0[_len_0] = fn(v)
      _len_0 = _len_0 + 1
    end
    return _accum_0
  end)(), getmetatable(t))
end
table.fork = function(t, values)
  return setmetatable(values or { }, {
    __index = t
  })
end
table.copy = function(t)
  return setmetatable((function()
    local _tbl_0 = { }
    for k, v in pairs(t) do
      _tbl_0[k] = v
    end
    return _tbl_0
  end)(), getmetatable(t))
end
local utf8_char_patt = (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"))
local operator_patt = S("'`~!@$^&*+=|<>?/-") ^ 1 * -1
local identifier_patt = (R("az", "AZ", "09") + P("_") + utf8_char_patt) ^ 1 * -1
local is_operator
is_operator = function(s)
  return not not operator_patt:match(s)
end
local is_identifier
is_identifier = function(s)
  return not not identifier_patt: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 = utf8_char_patt,
  escape = (function(self)
    return ("\\%03d"):format(self:byte())
  end)
})
local inline_escape
inline_escape = function(s)
  return inline_escaper:match(s)
end
local escaper = re.compile("{~ (%utf8_char / ('\\' -> '\\\\') / [\n\r\t -~] / (. -> escape))* ~}", {
  utf8_char = utf8_char_patt,
  escape = (function(self)
    return ("\\%03d"):format(self:byte())
  end)
})
local escape
escape = function(s)
  return escaper:match(s)
end
local make_tree
make_tree = function(tree, userdata)
  tree.source = Source(userdata.filename, tree.start, tree.stop)
  tree.start, tree.stop = nil, nil
  do
    local _accum_0 = { }
    local _len_0 = 1
    for _index_0 = 1, #tree do
      local t = tree[_index_0]
      if SyntaxTree:is_instance(t) and t.type == "Comment" then
        _accum_0[_len_0] = t
        _len_0 = _len_0 + 1
      end
    end
    tree.comments = _accum_0
  end
  if #tree.comments == 0 then
    tree.comments = nil
  end
  for i = #tree, 1, -1 do
    if SyntaxTree:is_instance(tree[i]) and tree[i].type == "Comment" then
      table.remove(tree, i)
    end
  end
  tree = SyntaxTree(tree)
  return tree
end
local Parsers = { }
local max_parser_version = 4
for version = 1, max_parser_version do
  local peg_file = io.open("nomsu." .. tostring(version) .. ".peg")
  if not peg_file and package.nomsupath then
    for path in package.nomsupath:gmatch("[^;]+") do
      peg_file = io.open(path .. "/nomsu." .. tostring(version) .. ".peg")
      if peg_file then
        break
      end
    end
  end
  assert(peg_file, "could not find nomsu .peg file")
  local peg_contents = peg_file:read('*a')
  peg_file:close()
  Parsers[version] = make_parser(peg_contents, make_tree)
end
local MAX_LINE = 80
local NomsuCompiler = setmetatable({ }, {
  __tostring = function(self)
    return "Nomsu"
  end
})
local _anon_chunk = 0
do
  NomsuCompiler.can_optimize = function()
    return false
  end
  NomsuCompiler.environment = {
    NOMSU_COMPILER_VERSION = 11,
    NOMSU_SYNTAX_VERSION = max_parser_version,
    next = next,
    unpack = unpack,
    setmetatable = setmetatable,
    coroutine = coroutine,
    rawequal = rawequal,
    getmetatable = getmetatable,
    pcall = pcall,
    error = error,
    package = package,
    os = os,
    require = require,
    tonumber = tonumber,
    tostring = tostring,
    string = string,
    xpcall = xpcall,
    module = module,
    print = print,
    loadfile = loadfile,
    rawset = rawset,
    _VERSION = _VERSION,
    collectgarbage = collectgarbage,
    rawget = rawget,
    rawlen = rawlen,
    table = table,
    assert = assert,
    dofile = dofile,
    loadstring = loadstring,
    lua_type_of = type,
    select = select,
    math = math,
    io = io,
    load = load,
    pairs = pairs,
    ipairs = ipairs,
    _List = List,
    _Dict = Dict,
    stringify = stringify,
    utils = utils,
    lpeg = lpeg,
    re = re,
    Files = Files,
    SyntaxTree = SyntaxTree,
    TESTS = Dict({ }),
    globals = Dict({ }),
    LuaCode = LuaCode,
    NomsuCode = NomsuCode,
    Source = Source,
    nomsu = NomsuCompiler,
    __imported = Dict({ }),
    __parent = nil
  }
  setmetatable(NomsuCompiler.environment, {
    __index = function(self, key)
      do
        local imported = rawget(self, "__imported")
        if imported then
          local ret = imported[key]
          if not (ret == nil) then
            return ret
          end
        end
      end
      do
        local parent = rawget(self, "__parent")
        if parent then
          return parent[key]
        end
      end
    end
  })
  if _VERSION == "Lua 5.4" then
    NomsuCompiler.environment.ipairs = function(x)
      do
        local mt = getmetatable(x)
        if mt then
          if mt.__ipairs then
            return mt.__ipairs(x)
          end
        end
      end
      return ipairs(x)
    end
  end
  if jit or _VERSION == "Lua 5.2" then
    NomsuCompiler.environment.bit = require("bitops")
  end
  NomsuCompiler.fork = function(self)
    local f = setmetatable({ }, {
      __index = self
    })
    f.environment = setmetatable({
      __parent = self.environment,
      __imported = Dict({ }),
      nomsu = f,
      COMPILE_ACTIONS = setmetatable({
        __parent = self.environment.COMPILE_ACTIONS,
        __imported = Dict({ })
      }, getmetatable(self.environment))
    }, getmetatable(self.environment))
    return f
  end
  NomsuCompiler.parse = function(self, nomsu_code, source, version)
    if source == nil then
      source = nil
    end
    if version == nil then
      version = nil
    end
    source = source or nomsu_code.source
    nomsu_code = tostring(nomsu_code)
    if not (source) then
      source = Source("anonymous chunk #" .. tostring(_anon_chunk), 1, #nomsu_code)
      _anon_chunk = _anon_chunk + 1
    end
    version = version or nomsu_code:match("^#![^\n]*nomsu[ ]+-V[ ]*([0-9.]+)")
    local syntax_version = version and tonumber(version:match("^[0-9]+")) or max_parser_version
    local parse = Parsers[syntax_version] or Parsers[max_parser_version]
    local tree = parse(nomsu_code, source.filename)
    local find_errors
    find_errors = function(t)
      if t.type == "Error" then
        return coroutine.yield(t)
      else
        for k, v in pairs(t) do
          local _continue_0 = false
          repeat
            if not (SyntaxTree:is_instance(v)) then
              _continue_0 = true
              break
            end
            find_errors(v)
            _continue_0 = true
          until true
          if not _continue_0 then
            break
          end
        end
      end
    end
    local errs
    do
      local _accum_0 = { }
      local _len_0 = 1
      for err in coroutine.wrap(function()
        return find_errors(tree)
      end) do
        _accum_0[_len_0] = err
        _len_0 = _len_0 + 1
      end
      errs = _accum_0
    end
    local num_errs = #errs
    if num_errs > 0 then
      local err_strings
      do
        local _accum_0 = { }
        local _len_0 = 1
        for i, t in ipairs(errs) do
          if i <= 3 then
            _accum_0[_len_0] = pretty_error({
              title = "Parse error",
              error = t.error,
              hint = t.hint,
              source = t:get_source_code(),
              start = t.source.start,
              stop = t.source.stop,
              filename = t.source.filename
            })
            _len_0 = _len_0 + 1
          end
        end
        err_strings = _accum_0
      end
      if num_errs > 3 then
        table.insert(err_strings, "\027[31;1m +" .. tostring(num_errs - #errs) .. " additional errors...\027[0m\n")
      end
      error(table.concat(err_strings, '\n\n'), 0)
    end
    return tree
  end
  NomsuCompiler.compile_error = function(self, tree, err_msg, hint)
    if hint == nil then
      hint = nil
    end
    local err_str = pretty_error({
      title = "Compile error",
      error = err_msg,
      hint = hint,
      source = tree:get_source_code(),
      start = tree.source.start,
      stop = tree.source.stop,
      filename = tree.source.filename
    })
    return error(err_str, 0)
  end
  local add_lua_bits
  add_lua_bits = function(self, val_or_stmt, code, compile_actions)
    local cls = val_or_stmt == "value" and LuaCode.Value or LuaCode
    local operate_on_text
    operate_on_text = function(text)
      local lua = cls(text.source)
      for _index_0 = 1, #text do
        local bit = text[_index_0]
        if type(bit) == "string" then
          lua:append(bit)
        elseif bit.type == "Text" then
          lua:append(operate_on_text(bit))
        else
          local bit_lua = self:compile(bit, compile_actions)
          if not (bit_lua.is_value) then
            self:compile_error(bit, "Can't use this as a string interpolation value, since it's not an expression.")
          end
          lua:append(bit_lua)
        end
      end
      return lua
    end
    return operate_on_text(code)
  end
  local add_lua_string_bits
  add_lua_string_bits = function(self, val_or_stmt, code)
    local cls_str = val_or_stmt == "value" and "LuaCode.Value(" or "LuaCode("
    if code.type ~= "Text" then
      return LuaCode.Value(code.source, cls_str, tostring(code.source):as_lua(), ", ", self:compile(code), ")")
    end
    local add_bit_lua
    add_bit_lua = function(lua, bit_lua)
      local bit_leading_len = #(bit_lua:match("^[^\n]*"))
      lua:append(lua:trailing_line_len() + bit_leading_len > MAX_LINE and ",\n    " or ", ")
      return lua:append(bit_lua)
    end
    local operate_on_text
    operate_on_text = function(text)
      local lua = LuaCode.Value(text.source, cls_str, tostring(text.source):as_lua())
      for _index_0 = 1, #text do
        local bit = text[_index_0]
        if type(bit) == "string" then
          add_bit_lua(lua, bit:as_lua())
        elseif bit.type == "Text" then
          add_bit_lua(lua, operate_on_text(bit))
        else
          local bit_lua = self:compile(bit)
          if not (bit_lua.is_value) then
            self:compile_error(bit, "Can't use this as a string interpolation value, since it's not an expression.")
          end
          add_bit_lua(lua, bit_lua)
        end
      end
      lua:append(")")
      return lua
    end
    return operate_on_text(code)
  end
  local math_expression = re.compile([[ (([*/^+-] / [0-9]+) " ")* [*/^+-] !. ]])
  local compile_math_expression
  compile_math_expression = function(self, tree, ...)
    local lua = LuaCode.Value(tree.source)
    for i, tok in ipairs(tree) do
      if type(tok) == 'string' then
        lua:append(tok)
      else
        local tok_lua = self:compile(tok, compile_actions)
        if not (tok_lua.is_value) then
          self:compile_error(tok, "Can't use this as a value in a math expression, since it's not a value.")
        end
        if tok.type == "Action" then
          tok_lua:parenthesize()
        end
        lua:append(tok_lua)
      end
      if i < #tree then
        lua:append(" ")
      end
    end
    return lua
  end
  NomsuCompiler.environment.COMPILE_ACTIONS = setmetatable({
    __imported = Dict({ }),
    ["Lua"] = function(self, tree, code)
      return add_lua_string_bits(self, 'statements', code)
    end,
    ["Lua value"] = function(self, tree, code)
      return add_lua_string_bits(self, 'value', code)
    end,
    ["lua >"] = function(self, tree, code)
      if code.type ~= "Text" then
        return LuaCode(tree.source, "nomsu:run_lua(", self:compile(code), ", nomsu);")
      end
      return add_lua_bits(self, "statements", code)
    end,
    ["= lua"] = function(self, tree, code)
      if code.type ~= "Text" then
        return LuaCode.Value(tree.source, "nomsu:run_lua(", self:compile(code), ":as_statements('return '), nomsu)")
      end
      return add_lua_bits(self, "value", code)
    end,
    ["use"] = function(self, tree, path)
      if path.type == 'Text' and #path == 1 and type(path[1]) == 'string' then
        if not (self:import_file(path[1])) then
          self:compile_error(tree, "Could not find anything to import for " .. tostring(path))
        end
      end
      return LuaCode(tree.source, "nomsu:import_file(" .. tostring(self:compile(path)) .. ")")
    end,
    ["tests"] = function(self, tree)
      return LuaCode.Value(tree.source, "TESTS")
    end,
    ["test"] = function(self, tree, body)
      local test_str = table.concat((function()
        local _accum_0 = { }
        local _len_0 = 1
        for _index_0 = 1, #body do
          local line = body[_index_0]
          _accum_0[_len_0] = tostring(self:tree_to_nomsu(line))
          _len_0 = _len_0 + 1
        end
        return _accum_0
      end)(), "\n")
      return LuaCode(tree.source, "TESTS[" .. tostring(tostring(tree.source):as_lua()) .. "] = ", test_str:as_lua())
    end,
    ["is jit"] = function(self, tree, code)
      return LuaCode.Value(tree.source, jit and "true" or "false")
    end,
    ["Lua version"] = function(self, tree, code)
      return LuaCode.Value(tree.source, _VERSION:as_lua())
    end,
    __parent = setmetatable({ }, {
      __index = function(self, key)
        if type(key) == 'string' and math_expression:match(key) then
          return compile_math_expression
        end
      end
    })
  }, getmetatable(NomsuCompiler.environment))
  NomsuCompiler.import = function(self, mod)
    for k, v in pairs(mod) do
      local _continue_0 = false
      repeat
        if k == "__imported" or k == "__parent" then
          _continue_0 = true
          break
        end
        self.environment.__imported[k] = v
        _continue_0 = true
      until true
      if not _continue_0 then
        break
      end
    end
    for k, v in pairs(mod.COMPILE_ACTIONS) do
      local _continue_0 = false
      repeat
        if k == "__imported" or k == "__parent" then
          _continue_0 = true
          break
        end
        self.environment.COMPILE_ACTIONS.__imported[k] = self.environment.COMPILE_ACTIONS.__imported[k] or v
        _continue_0 = true
      until true
      if not _continue_0 then
        break
      end
    end
  end
  NomsuCompiler.import_file = function(self, path)
    local found = false
    for _, f in Files.walk(path) do
      if match(f, "%.lua$") or match(f, "%.nom$") or match(f, "^/dev/fd/[012]$") then
        found = true
        self:import(self:run_file(f))
      end
    end
    return found
  end
  NomsuCompiler.run = function(self, to_run, compile_actions)
    local source = to_run.source or Source(to_run, 1, #to_run)
    if type(source) == 'string' then
      source = Source:from_string(source)
    end
    if not Files.read(source.filename) then
      Files.spoof(source.filename, to_run)
    end
    local tree
    if SyntaxTree:is_instance(to_run) then
      tree = to_run
    else
      tree = self:parse(to_run, source)
    end
    if tree == nil then
      return nil
    end
    if tree.type ~= "FileChunks" then
      tree = {
        tree
      }
    end
    local ret = nil
    local all_lua = { }
    for _index_0 = 1, #tree do
      local chunk = tree[_index_0]
      local lua = self:compile(chunk, compile_actions):as_statements("return ")
      lua:declare_locals()
      lua:prepend("-- File: " .. tostring(source.filename:gsub("\n.*", "...")) .. "\n")
      insert(all_lua, tostring(lua))
      ret = self:run_lua(lua)
    end
    return ret
  end
  local _running_files = { }
  local _loaded_files = { }
  NomsuCompiler.run_file = function(self, filename, compile_actions)
    if _loaded_files[filename] then
      return _loaded_files[filename]
    end
    for i, running in ipairs(_running_files) do
      if running == filename then
        local loop
        do
          local _accum_0 = { }
          local _len_0 = 1
          for j = i, #_running_files do
            _accum_0[_len_0] = _running_files[j]
            _len_0 = _len_0 + 1
          end
          loop = _accum_0
        end
        insert(loop, filename)
        error("Circular import, this loops forever: " .. tostring(concat(loop, " -> ")) .. "...")
      end
    end
    insert(_running_files, filename)
    local mod = self:fork()
    local ret = mod.environment
    mod.from_file = filename
    if match(filename, "%.lua$") then
      local file = assert(Files.read(filename), "Could not find file: " .. tostring(filename))
      ret = mod:run_lua(LuaCode(Source(filename, 1, #file), file)) or ret
    elseif match(filename, "%.nom$") or match(filename, "^/dev/fd/[012]$") then
      local ran_lua
      if self.can_optimize(filename) then
        local lua_filename = gsub(filename, "%.nom$", ".lua")
        do
          local file = Files.read(lua_filename)
          if file then
            ret = mod:run_lua(LuaCode(Source(lua_filename, 1, #file), file)) or ret
            ran_lua = true
          end
        end
      end
      if not (ran_lua) then
        local file = Files.read(filename)
        if not file then
          error("Tried to run file that does not exist: " .. tostring(filename))
        end
        ret = mod:run(NomsuCode(Source(filename, 1, #file), file), compile_actions) or ret
      end
    else
      error("Invalid filetype for " .. tostring(filename), 0)
    end
    _loaded_files[filename] = ret
    remove(_running_files)
    return ret
  end
  NomsuCompiler.run_lua = function(self, lua)
    local lua_string = tostring(lua)
    local run_lua_fn, err = load(lua_string, tostring(source or lua.source), "t", self.environment)
    if not run_lua_fn then
      local line_numbered_lua = concat((function()
        local _accum_0 = { }
        local _len_0 = 1
        for i, line in ipairs(Files.get_lines(lua_string)) do
          _accum_0[_len_0] = format("%3d|%s", i, line)
          _len_0 = _len_0 + 1
        end
        return _accum_0
      end)(), "\n")
      error("Failed to compile generated code:\n" .. tostring(colored.bright(colored.blue(colored.onblack(line_numbered_lua)))) .. "\n\n" .. tostring(err), 0)
    end
    local source = lua.source or Source(lua_string, 1, #lua_string)
    local source_key = tostring(source)
    if not (SOURCE_MAP[source_key]) then
      local map = { }
      local file = Files.read(source.filename)
      if not file then
        error("Failed to find file: " .. tostring(source.filename))
      end
      local nomsu_str = file:sub(source.start, source.stop)
      assert(type(nomsu_str) == 'string')
      local lua_line = 1
      local nomsu_line = Files.get_line_number(file, source.start)
      local map_sources
      map_sources = function(s)
        if type(s) == 'string' then
          for nl in s:gmatch("\n") do
            map[lua_line] = map[lua_line] or nomsu_line
            lua_line = lua_line + 1
          end
        else
          if s.source and s.source.filename == source.filename then
            nomsu_line = Files.get_line_number(file, s.source.start)
          end
          local _list_0 = s.bits
          for _index_0 = 1, #_list_0 do
            local b = _list_0[_index_0]
            map_sources(b)
          end
        end
      end
      map_sources(lua)
      map[lua_line] = map[lua_line] or nomsu_line
      map[0] = 0
      SOURCE_MAP[source_key] = map
    end
    return run_lua_fn()
  end
  NomsuCompiler.compile = function(self, tree, compile_actions, force_value)
    if force_value == nil then
      force_value = false
    end
    compile_actions = compile_actions or self.environment.COMPILE_ACTIONS
    if tree.version then
      do
        local get_version = self[("Nomsu version"):as_lua_id()]
        if get_version then
          do
            local upgrade = self[("1 upgraded from 2 to"):as_lua_id()]
            if upgrade then
              tree = upgrade(tree, tree.version, get_version())
            end
          end
        end
      end
    end
    local _exp_0 = tree.type
    if "Action" == _exp_0 then
      local stub = tree.stub
      local compile_action = compile_actions[stub]
      if compile_action and not tree.target then
        local args
        do
          local _accum_0 = { }
          local _len_0 = 1
          for _index_0 = 1, #tree do
            local arg = tree[_index_0]
            if type(arg) ~= "string" then
              _accum_0[_len_0] = arg
              _len_0 = _len_0 + 1
            end
          end
          args = _accum_0
        end
        local ret = compile_action(self, tree, unpack(args))
        if ret == nil then
          local info = debug.getinfo(compile_action, "S")
          local filename = Source:from_string(info.source).filename
          self:compile_error(tree, "The compile-time action here (" .. tostring(stub) .. ") failed to return any value.", "Look at the implementation of (" .. tostring(stub) .. ") in " .. tostring(filename) .. ":" .. tostring(info.linedefined) .. " and make sure it's returning something.")
        end
        if SyntaxTree:is_instance(ret) then
          if ret == tree then
            local info = debug.getinfo(compile_action, "S")
            local filename = Source:from_string(info.source).filename
            self:compile_error(tree, "The compile-time action here (" .. tostring(stub) .. ") is producing an endless loop.", "Look at the implementation of (" .. tostring(stub) .. ") in " .. tostring(filename) .. ":" .. tostring(info.linedefined) .. " and make sure it's not just returning the original tree.")
          end
          return self:compile(ret, compile_actions)
        end
        return ret
      end
      local lua = LuaCode.Value(tree.source)
      if tree.target then
        local target_lua = self:compile(tree.target, compile_actions)
        if tostring(target_lua):match("^%(.*%)$") or tostring(target_lua):match("^[_a-zA-Z][_a-zA-Z0-9]*$") then
          lua:append(target_lua, ":")
        else
          lua:append("(", target_lua, "):")
        end
      end
      lua:append((stub):as_lua_id(), "(")
      local args = { }
      for i, tok in ipairs(tree) do
        local _continue_0 = false
        repeat
          if type(tok) == "string" then
            _continue_0 = true
            break
          end
          local arg_lua = self:compile(tok, compile_actions, true)
          if not (arg_lua.is_value) then
            if tok.type == "Block" then
              self:compile_error(tok, "Can't compile action (" .. tostring(stub) .. ") with a Block as an argument.", "Maybe there should be a compile-time action with that name that isn't being found?")
            elseif tok.type == "Action" then
              self:compile_error(tok, "Can't use this as an argument to (" .. tostring(stub) .. "), since it's not an expression, it produces: " .. tostring(tostring(arg_lua)), "Check the implementation of (" .. tostring(tok.stub) .. ") to see if it is actually meant to produce an expression.")
            else
              self:compile_error(tok, "Can't use this as an argument to (" .. tostring(stub) .. "), since it's not an expression, it produces: " .. tostring(tostring(arg_lua)))
            end
          end
          insert(args, arg_lua)
          _continue_0 = true
        until true
        if not _continue_0 then
          break
        end
      end
      lua:concat_append(args, ", ")
      lua:append(")")
      return lua
    elseif "EscapedNomsu" == _exp_0 then
      local lua = LuaCode.Value(tree.source, "SyntaxTree{")
      local needs_comma, i = false, 1
      local as_lua
      as_lua = function(x)
        if type(x) == 'number' then
          return tostring(x)
        elseif SyntaxTree:is_instance(x) then
          return self:compile(x, compile_actions)
        else
          return x:as_lua()
        end
      end
      for k, v in pairs((SyntaxTree:is_instance(tree[1]) and tree[1].type == "EscapedNomsu" and tree) or tree[1]) do
        if needs_comma then
          lua:append(", ")
        else
          needs_comma = true
        end
        if k == i then
          i = i + 1
        elseif type(k) == 'string' and match(k, "[_a-zA-Z][_a-zA-Z0-9]*") then
          lua:append(k, "= ")
        else
          lua:append("[", as_lua(k), "]= ")
        end
        if k == "source" then
          lua:append(tostring(v):as_lua())
        else
          lua:append(as_lua(v))
        end
      end
      lua:append("}")
      return lua
    elseif "Block" == _exp_0 then
      if not force_value then
        local lua = LuaCode(tree.source)
        lua:concat_append((function()
          local _accum_0 = { }
          local _len_0 = 1
          for _index_0 = 1, #tree do
            local line = tree[_index_0]
            _accum_0[_len_0] = self:compile(line, compile_actions):as_statements()
            _len_0 = _len_0 + 1
          end
          return _accum_0
        end)(), "\n")
        return lua
      else
        local lua = LuaCode.Value(tree.source)
        local values
        do
          local _accum_0 = { }
          local _len_0 = 1
          for _index_0 = 1, #tree do
            local line = tree[_index_0]
            _accum_0[_len_0] = self:compile(line)
            _len_0 = _len_0 + 1
          end
          values = _accum_0
        end
        local all_values = true
        for _index_0 = 1, #values do
          local v = values[_index_0]
          all_values = all_values and v.is_value
        end
        if all_values then
          if #values == 1 then
            return values[1]
          end
          lua:append("(")
          lua:concat_append(values, " and nil or ")
          lua:append(")")
        else
          lua:append("((function()")
          for i, v in ipairs(values) do
            if v.is_value then
              v = v:as_statements(i == #values and 'return ' or '')
            end
            lua:append("\n    ", v)
          end
          lua:append("\nend)())")
        end
        return lua
      end
    elseif "Text" == _exp_0 then
      local lua = LuaCode.Value(tree.source)
      local string_buffer = ""
      for i, bit in ipairs(tree) do
        local _continue_0 = false
        repeat
          if type(bit) == "string" then
            string_buffer = string_buffer .. bit
            _continue_0 = true
            break
          end
          if string_buffer ~= "" then
            if #lua.bits > 0 then
              lua:append("..")
            end
            lua:append(string_buffer:as_lua())
            string_buffer = ""
          end
          local bit_lua = self:compile(bit, compile_actions)
          if not (bit_lua.is_value) then
            local src = '    ' .. gsub(tostring(self:compile(bit, compile_actions)), '\n', '\n    ')
            local line = tostring(bit.source.filename) .. ":" .. tostring(Files.get_line_number(Files.read(bit.source.filename), bit.source.start))
            self:compile_error(bit, "Can't this as a string interpolation value, since it's not an expression.")
          end
          if #lua.bits > 0 then
            lua:append("..")
          end
          if bit.type ~= "Text" then
            bit_lua = LuaCode.Value(bit.source, "stringify(", bit_lua, ")")
          end
          lua:append(bit_lua)
          _continue_0 = true
        until true
        if not _continue_0 then
          break
        end
      end
      if string_buffer ~= "" or #lua.bits == 0 then
        if #lua.bits > 0 then
          lua:append("..")
        end
        lua:append(string_buffer:as_lua())
      end
      if #lua.bits > 1 then
        lua:parenthesize()
      end
      return lua
    elseif "List" == _exp_0 then
      local lua = LuaCode.Value(tree.source, "_List{")
      lua:concat_append((function()
        local _accum_0 = { }
        local _len_0 = 1
        for _index_0 = 1, #tree do
          local e = tree[_index_0]
          _accum_0[_len_0] = self:compile(e, compile_actions)
          _len_0 = _len_0 + 1
        end
        return _accum_0
      end)(), ", ", ",\n  ")
      lua:append("}")
      return lua
    elseif "Dict" == _exp_0 then
      local lua = LuaCode.Value(tree.source, "_Dict{")
      lua:concat_append((function()
        local _accum_0 = { }
        local _len_0 = 1
        for _index_0 = 1, #tree do
          local e = tree[_index_0]
          _accum_0[_len_0] = self:compile(e, compile_actions)
          _len_0 = _len_0 + 1
        end
        return _accum_0
      end)(), ", ", ",\n  ")
      lua:append("}")
      return lua
    elseif "DictEntry" == _exp_0 then
      local key, value = tree[1], tree[2]
      local key_lua = self:compile(key, compile_actions)
      if not (key_lua.is_value) then
        self:compile_error(tree[1], "Can't use this as a dict key, since it's not an expression.")
      end
      local value_lua = value and self:compile(value, compile_actions) or LuaCode.Value(key.source, "true")
      if not (value_lua.is_value) then
        self:compile_error(tree[2], "Can't use this as a dict value, since it's not an expression.")
      end
      local key_str = match(tostring(key_lua), [=[^["']([a-zA-Z_][a-zA-Z0-9_]*)['"]$]=])
      if key_str and key_str:is_lua_id() then
        return LuaCode(tree.source, key_str, "=", value_lua)
      elseif sub(tostring(key_lua), 1, 1) == "[" then
        return LuaCode(tree.source, "[ ", key_lua, "]=", value_lua)
      else
        return LuaCode(tree.source, "[", key_lua, "]=", value_lua)
      end
    elseif "IndexChain" == _exp_0 then
      local lua = self:compile(tree[1], compile_actions)
      if not (lua.is_value) then
        self:compile_error(tree[1], "Can't index into this, since it's not an expression.")
      end
      local first_char = sub(tostring(lua), 1, 1)
      if first_char == "{" or first_char == '"' or first_char == "[" then
        lua:parenthesize()
      end
      for i = 2, #tree do
        local key = tree[i]
        local key_lua = self:compile(key, compile_actions)
        if not (key_lua.is_value) then
          self:compile_error(key, "Can't use this as an index, since it's not an expression.")
        end
        local key_lua_str = tostring(key_lua)
        local lua_id = match(key_lua_str, "^['\"]([a-zA-Z_][a-zA-Z0-9_]*)['\"]$")
        if lua_id and lua_id:is_lua_id() then
          lua:append("." .. tostring(lua_id))
        elseif sub(key_lua_str, 1, 1) == '[' then
          lua:append("[ ", key_lua, " ]")
        else
          lua:append("[", key_lua, "]")
        end
      end
      return lua
    elseif "Number" == _exp_0 then
      return LuaCode.Value(tree.source, tostring(tree[1]))
    elseif "Var" == _exp_0 then
      return LuaCode.Value(tree.source, (tree[1]):as_lua_id())
    elseif "FileChunks" == _exp_0 then
      return error("Can't convert FileChunks to a single block of lua, since each chunk's " .. "compilation depends on the earlier chunks")
    elseif "Comment" == _exp_0 then
      return LuaCode(tree.source, "")
    elseif "Error" == _exp_0 then
      return error("Can't compile errors")
    else
      return error("Unknown type: " .. tostring(tree.type))
    end
  end
  NomsuCompiler.tree_to_inline_nomsu = function(self, tree, parenthesize_blocks, check, len)
    if parenthesize_blocks == nil then
      parenthesize_blocks = false
    end
    if check == nil then
      check = nil
    end
    if len == nil then
      len = 0
    end
    local recurse
    recurse = function(tree, nomsu, parenthesize_blocks)
      if nomsu == nil then
        nomsu = nil
      end
      if parenthesize_blocks == nil then
        parenthesize_blocks = false
      end
      return self:tree_to_inline_nomsu(tree, parenthesize_blocks, check, len + (nomsu and #tostring(nomsu) or 0))
    end
    local _exp_0 = tree.type
    if "FileChunks" == _exp_0 then
      return error("Can't inline a FileChunks")
    elseif "Comment" == _exp_0 then
      return NomsuCode(tree.source, "")
    elseif "Error" == _exp_0 then
      return error("Can't compile errors")
    elseif "Action" == _exp_0 then
      local nomsu = NomsuCode(tree.source)
      if tree.target then
        local inline_target = self:tree_to_inline_nomsu(tree.target)
        if tree.target.type == "Action" then
          inline_target:parenthesize()
        end
        nomsu:append(inline_target, "::")
      end
      for i, bit in ipairs(tree) do
        if type(bit) == "string" then
          local clump_words = (type(tree[i - 1]) == 'string' and is_operator(bit) ~= is_operator(tree[i - 1]))
          if i > 1 and not clump_words then
            nomsu:append(" ")
          end
          nomsu:append(bit)
        else
          local arg_nomsu = recurse(bit, nomsu, parenthesize_blocks or (i == 1 or i < #tree))
          if not (arg_nomsu:match("^:") or i == 1) then
            nomsu:append(" ")
          end
          if bit.type == "Action" then
            arg_nomsu:parenthesize()
          end
          nomsu:append(arg_nomsu)
        end
        if check then
          check(len, nomsu, tree)
        end
      end
      return nomsu
    elseif "EscapedNomsu" == _exp_0 then
      local inner_nomsu = recurse(tree[1])
      if not (tree[1].type == "List" or tree[1].type == "Dict" or tree[1].type == "Var") then
        inner_nomsu:parenthesize()
      end
      local nomsu = NomsuCode(tree.source, "\\", inner_nomsu)
      if check then
        check(len, nomsu, tree)
      end
      return nomsu
    elseif "Block" == _exp_0 then
      local nomsu = NomsuCode(tree.source, ":")
      if check then
        check(len, nomsu, tree)
      end
      for i, line in ipairs(tree) do
        nomsu:append(i == 1 and " " or "; ")
        nomsu:append(recurse(line, nomsu, i == 1 or i < #tree))
        if check then
          check(len, nomsu, tree)
        end
      end
      if #tree > 1 or parenthesize_blocks then
        nomsu:parenthesize()
      end
      return nomsu
    elseif "Text" == _exp_0 then
      local add_text
      add_text = function(nomsu, tree)
        for i, bit in ipairs(tree) do
          if type(bit) == 'string' then
            local escaped = inline_escape(bit)
            nomsu:append(inline_escape(bit))
          elseif bit.type == "Text" then
            add_text(nomsu, bit)
          else
            local interp_nomsu = recurse(bit, nomsu)
            if bit.type ~= "Var" and bit.type ~= "List" and bit.type ~= "Dict" then
              interp_nomsu:parenthesize()
            elseif bit.type == "Var" and type(tree[i + 1]) == 'string' and not match(tree[i + 1], "^[ \n\t,.:;#(){}[%]]") then
              interp_nomsu:parenthesize()
            end
            nomsu:append("\\", interp_nomsu)
          end
          if check then
            check(len, nomsu, tree)
          end
        end
      end
      local nomsu = NomsuCode(tree.source)
      add_text(nomsu, tree)
      return NomsuCode(tree.source, '"', nomsu, '"')
    elseif "List" == _exp_0 or "Dict" == _exp_0 then
      local nomsu = NomsuCode(tree.source, (tree.type == "List" and "[" or "{"))
      for i, item in ipairs(tree) do
        if i > 1 then
          nomsu:append(", ")
        end
        nomsu:append(recurse(item, nomsu))
        if check then
          check(len, nomsu, tree)
        end
      end
      nomsu:append(tree.type == "List" and "]" or "}")
      return nomsu
    elseif "DictEntry" == _exp_0 then
      local key, value = tree[1], tree[2]
      local nomsu
      if key.type == "Text" and #key == 1 and is_identifier(key[1]) then
        nomsu = NomsuCode(key.source, key[1])
      else
        nomsu = recurse(key)
      end
      if key.type == "Action" or key.type == "Block" then
        nomsu:parenthesize()
      end
      assert(value.type ~= "Block", "Didn't expect to find a Block as a value in a dict")
      nomsu:append(":")
      if value then
        local value_nomsu = recurse(value, nomsu)
        if value.type == "Block" then
          value_nomsu:parenthesize()
        end
        nomsu:append(value_nomsu)
      end
      if check then
        check(len, nomsu, tree)
      end
      return nomsu
    elseif "IndexChain" == _exp_0 then
      local nomsu = NomsuCode(tree.source)
      for i, bit in ipairs(tree) do
        if i > 1 then
          nomsu:append(".")
        end
        local bit_nomsu
        if i > 1 and bit.type == "Text" and #bit == 1 and type(bit[1]) == 'string' and is_identifier(bit[1]) then
          bit_nomsu = bit[1]
        else
          bit_nomsu = recurse(bit, nomsu)
        end
        assert(bit.type ~= "Block")
        if bit.type == "Action" or bit.type == "IndexChain" or (bit.type == "Number" and i < #tree) then
          bit_nomsu:parenthesize()
        end
        nomsu:append(bit_nomsu)
        if check then
          check(len, nomsu, tree)
        end
      end
      return nomsu
    elseif "Number" == _exp_0 then
      return NomsuCode(tree.source, tostring(tree[1]))
    elseif "Var" == _exp_0 then
      return NomsuCode(tree.source, "%", tree[1])
    else
      return error("Unknown type: " .. tostring(tree.type))
    end
  end
  NomsuCompiler.tree_to_nomsu = function(self, tree, pop_comments)
    if pop_comments == nil then
      pop_comments = nil
    end
    if not (pop_comments) then
      local comment_set = { }
      local find_comments
      find_comments = function(t)
        if t.comments and t.source.filename == tree.source.filename then
          local _list_0 = t.comments
          for _index_0 = 1, #_list_0 do
            local c = _list_0[_index_0]
            comment_set[c] = true
          end
        end
        local _list_0 = t
        for _index_0 = 1, #_list_0 do
          local x = _list_0[_index_0]
          if SyntaxTree:is_instance(x) then
            find_comments(x)
          end
        end
      end
      find_comments(tree)
      local comments
      do
        local _accum_0 = { }
        local _len_0 = 1
        for c in pairs(comment_set) do
          _accum_0[_len_0] = c
          _len_0 = _len_0 + 1
        end
        comments = _accum_0
      end
      table.sort(comments, function(a, b)
        return (a.source.start > b.source.start)
      end)
      pop_comments = function(pos, prefix, suffix)
        if prefix == nil then
          prefix = ''
        end
        if suffix == nil then
          suffix = ''
        end
        local nomsu = NomsuCode(tree.source)
        for i = #comments, 1, -1 do
          if comments[i].source.start > pos then
            break
          end
          local comment
          comment, comments[i] = comments[i][1], nil
          nomsu:append("#" .. (gsub(comment, "\n", "\n    ")) .. "\n")
          if comment:match("^\n.") then
            nomsu:append("\n")
          end
        end
        if #nomsu.bits == 0 then
          return ''
        end
        if not (prefix == '') then
          nomsu:prepend(prefix)
        end
        if not (suffix == '') then
          nomsu:append(suffix)
        end
        return nomsu
      end
    end
    local recurse
    recurse = function(t, pos)
      if pos == nil then
        pos = 0
      end
      if type(pos) ~= 'number' then
        pos = #tostring(pos):match("[ ]*([^\n]*)$")
      end
      local space = MAX_LINE - pos
      local inline
      for prefix, nomsu, tree in coroutine.wrap(function()
        inline = self:tree_to_inline_nomsu(t, false, coroutine.yield)
      end) do
        local len = #tostring(nomsu)
        if prefix + len > MAX_LINE then
          break
        end
        if tree.type == "Block" and (#tree > 1 or len > 20) then
          break
        end
        if tree.type == "Text" then
          local check_for_nl
          check_for_nl = function(tree)
            local found_nl = false
            for i, b in ipairs(tree) do
              if type(b) ~= 'string' and b.type == "Text" and check_for_nl(b) then
                return true
              end
              if i == 1 and type(b) == 'string' then
                b = b:match('^[\n]*(.*)')
              end
              found_nl = found_nl or (type(b) == 'string' and b:match('\n'))
              if found_nl and (type(b) ~= 'string' or b:match('[^\n]')) then
                return true
              end
            end
          end
          if check_for_nl(tree) then
            break
          end
        end
      end
      if inline and #tostring(inline) <= space then
        return inline
      end
      local indented = self:tree_to_nomsu(t, pop_comments, space)
      if t.type == "Action" and not (tree.type == "Block" or tree.type == "FileChunks") then
        indented = NomsuCode(t.source, "(..)\n    ", pop_comments(t.source.start), indented)
      end
      return indented
    end
    local _exp_0 = tree.type
    if "FileChunks" == _exp_0 then
      local nomsu = NomsuCode(tree.source, pop_comments(tree.source.start))
      local should_clump
      should_clump = function(prev_line, line)
        if prev_line.type == "Action" and line.type == "Action" then
          if prev_line.stub == "use" then
            return line.stub == "use"
          end
          if prev_line.stub == "test" then
            return true
          end
          if line.stub == "test" then
            return false
          end
        end
        return not recurse(prev_line):is_multiline()
      end
      for chunk_no, chunk in ipairs(tree) do
        if chunk_no > 1 then
          nomsu:append("\n\n" .. tostring(("~"):rep(80)) .. "\n\n")
        end
        nomsu:append(pop_comments(chunk.source.start))
        if chunk.type == "Block" then
          for line_no, line in ipairs(chunk) do
            if line_no > 1 then
              if should_clump(chunk[line_no - 1], line) then
                nomsu:append("\n", pop_comments(line.source.start, '\n'))
              else
                nomsu:append("\n\n", pop_comments(line.source.start))
              end
            end
            nomsu:append(self:tree_to_nomsu(line, pop_comments))
          end
          nomsu:append(pop_comments(chunk.source.stop, '\n'))
        else
          nomsu:append(recurse(chunk))
        end
      end
      nomsu:append(pop_comments(tree.source.stop, '\n'))
      if not (nomsu:match("\n$")) then
        nomsu:append('\n')
      end
      return nomsu
    elseif "Action" == _exp_0 then
      local pos, next_space = tree.source.start, ''
      local nomsu = NomsuCode(tree.source, pop_comments(pos))
      if tree.target then
        if tree.target.type == "Block" then
          nomsu:append(recurse(tree.target, #nomsu:match('[^\n]*$')))
          pos = tree.target.source.stop
          next_space = inline and "::" or "\n..::"
        else
          local target_nomsu = recurse(tree.target, #nomsu:match('[^\n]*$'))
          if tree.target.type == "Action" and not target_nomsu:is_multiline() then
            target_nomsu:parenthesize()
          end
          nomsu:append(target_nomsu)
          pos = tree.target.source.stop
          next_space = target_nomsu:is_multiline() and "\n..::" or "::"
        end
      end
      for i, bit in ipairs(tree) do
        if next_space == "\n.." then
          nomsu:append("\n", pop_comments(pos), '..')
          next_space = ""
        elseif next_space == " " and nomsu:trailing_line_len() > MAX_LINE then
          nomsu:append(" \\\n", pop_comments(pos), '..')
          next_space = ""
        end
        if type(bit) == "string" then
          if not (type(tree[i - 1]) == 'string' and is_operator(tree[i - 1]) ~= is_operator(bit)) then
            nomsu:append(next_space)
          end
          nomsu:append(bit)
          next_space = ' '
        elseif bit.type == "Block" then
          nomsu:append(recurse(bit, #nomsu:match('[^\n]*$')))
          pos = bit.source.stop
          next_space = inline and " " or "\n.."
        else
          nomsu:append(next_space)
          local bit_nomsu = recurse(bit, #nomsu:match('[^\n]*$'))
          if bit.type == "Action" and not bit_nomsu:is_multiline() then
            bit_nomsu:parenthesize()
          end
          nomsu:append(bit_nomsu)
          pos = bit.source.stop
          next_space = bit_nomsu:is_multiline() and "\n.." or " "
        end
      end
      nomsu:append(pop_comments(tree.source.stop, '\n'))
      return nomsu
    elseif "EscapedNomsu" == _exp_0 then
      local val_nomsu = recurse(tree[1], 1)
      if tree[1].type == "Action" and not val_nomsu:is_multiline() then
        val_nomsu:parenthesize()
      end
      return NomsuCode(tree.source, "\\", val_nomsu)
    elseif "Block" == _exp_0 then
      local nomsu = NomsuCode(tree.source, pop_comments(tree.source.start))
      for i, line in ipairs(tree) do
        nomsu:append(pop_comments(line.source.start, i > 1 and '\n' or ''))
        local line_nomsu = recurse(line)
        nomsu:append(line_nomsu)
        if i < #tree then
          nomsu:append(line_nomsu:match('\n[^\n]*\n') and "\n\n" or "\n")
        end
      end
      nomsu:append(pop_comments(tree.source.stop, '\n'))
      return NomsuCode(tree.source, ":\n    ", nomsu)
    elseif "Text" == _exp_0 then
      local max_line = math.floor(1.5 * MAX_LINE)
      local add_text
      add_text = function(nomsu, tree)
        for i, bit in ipairs(tree) do
          if type(bit) == 'string' then
            bit = escape(bit)
            local bit_lines = Files.get_lines(bit)
            for j, line in ipairs(bit_lines) do
              if j > 1 then
                nomsu:append("\n")
              elseif #line > 10 and nomsu:trailing_line_len() > max_line then
                nomsu:append("\\\n..")
              end
              while #line > 0 do
                local space = max_line - nomsu:trailing_line_len()
                local split = find(line, "[%p%s]", space)
                if not split or split > space + 10 then
                  split = space + 10
                end
                if #line - split < 10 then
                  split = #line
                end
                local bite
                bite, line = sub(line, 1, split), sub(line, split + 1, -1)
                nomsu:append(bite)
                if #line > 0 then
                  nomsu:append("\\\n..")
                end
              end
            end
          elseif bit.type == "Text" then
            add_text(nomsu, bit)
          else
            nomsu:append("\\")
            local interp_nomsu = recurse(bit, #nomsu:match('[^\n]*$'))
            if not (interp_nomsu:is_multiline()) then
              if bit.type == "Var" then
                if type(tree[i + 1]) == 'string' and not match(tree[i + 1], "^[ \n\t,.:;#(){}[%]]") then
                  interp_nomsu:parenthesize()
                end
              elseif bit.type ~= "List" and bit.type ~= "Dict" then
                interp_nomsu:parenthesize()
              end
            end
            nomsu:append(interp_nomsu)
            if interp_nomsu:is_multiline() then
              nomsu:append("\n..")
            end
          end
        end
      end
      local nomsu = NomsuCode(tree.source)
      add_text(nomsu, tree)
      return NomsuCode(tree.source, '"\\\n    ..', nomsu, '"')
    elseif "List" == _exp_0 or "Dict" == _exp_0 then
      assert(#tree > 0)
      local nomsu = NomsuCode(tree.source, pop_comments(tree[1].source.start))
      for i, item in ipairs(tree) do
        if nomsu:trailing_line_len() == 0 then
          nomsu:append(pop_comments(item.source.start))
        end
        local inline_nomsu = self:tree_to_inline_nomsu(item)
        local item_nomsu = #tostring(inline_nomsu) <= MAX_LINE and inline_nomsu or recurse(item, #nomsu:match('[^\n]*$'))
        nomsu:append(item_nomsu)
        if i < #tree then
          nomsu:append((item_nomsu:is_multiline() or nomsu:trailing_line_len() + #tostring(item_nomsu) >= MAX_LINE) and '\n' or ', ')
        end
      end
      nomsu:append(pop_comments(tree.source.stop, '\n'))
      if tree.type == "List" then
        return NomsuCode(tree.source, "[..]\n    ", nomsu)
      else
        return NomsuCode(tree.source, "{..}\n    ", nomsu)
      end
    elseif "DictEntry" == _exp_0 then
      local key, value = tree[1], tree[2]
      local nomsu
      if key.type == "Text" and #key == 1 and is_identifier(key[1]) then
        nomsu = NomsuCode(key.source, key[1])
      else
        nomsu = self:tree_to_inline_nomsu(key)
      end
      if key.type == "Action" or key.type == "Block" then
        nomsu:parenthesize()
      end
      nomsu:append(": ", recurse(value, #tostring(nomsu)))
      return nomsu
    elseif "IndexChain" == _exp_0 or "Number" == _exp_0 or "Var" == _exp_0 or "Comment" == _exp_0 or "Error" == _exp_0 then
      return self:tree_to_inline_nomsu(tree)
    else
      return error("Unknown type: " .. tostring(tree.type))
    end
  end
end
return NomsuCompiler