Moved error logic into its own file.

error_handling.lua

@@ -0,0 +1,214 @@
+local debug_getinfo = debug.getinfo
+local ok, to_lua = pcall(function()
+  return require('moonscript.base').to_lua
+end)
+if not ok then
+  to_lua = nil
+end
+local moonscript_line_tables = setmetatable({ }, {
+  __index = function(self, filename)
+    if not (to_lua) then
+      return nil
+    end
+    local _, line_table = to_lua(FILE_CACHE[filename])
+    self[filename] = line_table
+    return line_table
+  end
+})
+debug.getinfo = function(thread, f, what)
+  if what == nil then
+    f, what, thread = thread, f, nil
+  end
+  if type(f) == 'number' then
+    f = f + 1
+  end
+  local info
+  if thread == nil then
+    info = debug_getinfo(f, what)
+  else
+    info = debug_getinfo(thread, f, what)
+  end
+  if not info or not info.func then
+    return info
+  end
+  if info.short_src or info.source or info.linedefine or info.currentline then
+    do
+      local map = SOURCE_MAP[info.source]
+      if map then
+        if info.currentline then
+          info.currentline = assert(map[info.currentline])
+        end
+        if info.linedefined then
+          info.linedefined = assert(map[info.linedefined])
+        end
+        if info.lastlinedefined then
+          info.lastlinedefined = assert(map[info.lastlinedefined])
+        end
+        info.short_src = info.source:match('@([^[]*)') or info.short_src
+      end
+    end
+  end
+  return info
+end
+local print_err_msg
+print_err_msg = function(error_message, stack_offset)
+  if stack_offset == nil then
+    stack_offset = 3
+  end
+  io.stderr:write(tostring(colored.red("ERROR:")) .. " " .. tostring(colored.bright(colored.red((error_message or "")))) .. "\n")
+  io.stderr:write("stack traceback:\n")
+  ok, to_lua = pcall(function()
+    return require('moonscript.base').to_lua
+  end)
+  if not ok then
+    to_lua = function()
+      return nil
+    end
+  end
+  local LINE_TABLES = setmetatable({ }, {
+    __index = function(self, file)
+      local _, line_table = to_lua(file)
+      self[file] = line_table or false
+      return line_table or false
+    end
+  })
+  local get_line
+  get_line = function(file, line_no)
+    local start = LINE_STARTS[file][line_no] or 1
+    local stop = (LINE_STARTS[file][line_no + 1] or 0) - 1
+    return file:sub(start, stop)
+  end
+  local level = stack_offset
+  while true do
+    local _continue_0 = false
+    repeat
+      local calling_fn = debug_getinfo(level)
+      if not calling_fn then
+        break
+      end
+      if calling_fn.func == run then
+        break
+      end
+      level = level + 1
+      local name = calling_fn.name and "function '" .. tostring(calling_fn.name) .. "'" or nil
+      if calling_fn.linedefined == 0 then
+        name = "main chunk"
+      end
+      if name == "run_lua_fn" then
+        _continue_0 = true
+        break
+      end
+      local line = nil
+      do
+        local map = SOURCE_MAP[calling_fn.source]
+        if map then
+          if calling_fn.currentline then
+            calling_fn.currentline = assert(map[calling_fn.currentline])
+          end
+          if calling_fn.linedefined then
+            calling_fn.linedefined = assert(map[calling_fn.linedefined])
+          end
+          if calling_fn.lastlinedefined then
+            calling_fn.lastlinedefined = assert(map[calling_fn.lastlinedefined])
+          end
+          local filename, start, stop = calling_fn.source:match('@([^[]*)%[([0-9]+):([0-9]+)]')
+          assert(filename)
+          local file = FILE_CACHE[filename]:sub(tonumber(start), tonumber(stop))
+          local err_line = get_line(file, calling_fn.currentline):sub(1, -2)
+          local offending_statement = colored.bright(colored.red(err_line:match("^[ ]*(.*)")))
+          name = "action '" .. tostring(calling_fn.name) .. "'"
+          line = colored.yellow(tostring(filename) .. ":" .. tostring(calling_fn.currentline) .. " in " .. tostring(name) .. "\n        " .. tostring(offending_statement))
+        else
+          local file
+          ok, file = pcall(function()
+            return FILE_CACHE[calling_fn.short_src]
+          end)
+          if not ok then
+            file = nil
+          end
+          local line_num
+          if name == nil then
+            local search_level = level
+            local _info = debug.getinfo(search_level)
+            while _info and (_info.func == pcall or _info.func == xpcall) do
+              search_level = search_level + 1
+              _info = debug.getinfo(search_level)
+            end
+            if _info then
+              for i = 1, 999 do
+                local varname, val = debug.getlocal(search_level, i)
+                if not varname then
+                  break
+                end
+                if val == calling_fn.func then
+                  name = "local '" .. tostring(varname) .. "'"
+                  if not varname:match("%(") then
+                    break
+                  end
+                end
+              end
+              if not (name) then
+                for i = 1, _info.nups do
+                  local varname, val = debug.getupvalue(_info.func, i)
+                  if not varname then
+                    break
+                  end
+                  if val == calling_fn.func then
+                    name = "upvalue '" .. tostring(varname) .. "'"
+                    if not varname:match("%(") then
+                      break
+                    end
+                  end
+                end
+              end
+            end
+          end
+          if file and calling_fn.short_src:match(".moon$") and LINE_TABLES[file] then
+            local char = LINE_TABLES[file][calling_fn.currentline]
+            line_num = 1
+            for _ in file:sub(1, char):gmatch("\n") do
+              line_num = line_num + 1
+            end
+            line = colored.cyan(tostring(calling_fn.short_src) .. ":" .. tostring(line_num) .. " in " .. tostring(name or '?'))
+          else
+            line_num = calling_fn.currentline
+            if calling_fn.short_src == '[C]' then
+              line = colored.green(tostring(calling_fn.short_src) .. " in " .. tostring(name or '?'))
+            else
+              line = colored.blue(tostring(calling_fn.short_src) .. ":" .. tostring(calling_fn.currentline) .. " in " .. tostring(name or '?'))
+            end
+          end
+          if file then
+            local err_line = get_line(file, line_num):sub(1, -2)
+            local offending_statement = colored.bright(colored.red(err_line:match("^[ ]*(.*)$")))
+            line = line .. ("\n        " .. offending_statement)
+          end
+        end
+      end
+      io.stderr:write("    " .. tostring(line) .. "\n")
+      if calling_fn.istailcall then
+        io.stderr:write("    " .. tostring(colored.dim(colored.white("  (...tail calls...)"))) .. "\n")
+      end
+      _continue_0 = true
+    until true
+    if not _continue_0 then
+      break
+    end
+  end
+  return io.stderr:flush()
+end
+local err_hand
+err_hand = function(error_message)
+  print_err_msg(error_message)
+  return os.exit(false, true)
+end
+local has_ldt, ldt = pcall(require, 'ldt')
+local safe_run
+if has_ldt then
+  safe_run = ldt.guard
+else
+  safe_run = function(fn)
+    return xpcall(fn, err_hand)
+  end
+end
+return safe_run

error_handling.moon

@@ -0,0 +1,143 @@
+-- This file contains the logic for making nicer error messages
+debug_getinfo = debug.getinfo
+export SOURCE_MAP
+
+ok, to_lua = pcall -> require('moonscript.base').to_lua
+if not ok then to_lua = nil
+moonscript_line_tables = setmetatable {}, {
+    __index: (filename)=>
+        return nil unless to_lua
+        _, line_table = to_lua(FILE_CACHE[filename])
+        self[filename] = line_table
+        return line_table
+}
+
+-- Make a better version of debug.getinfo that provides info about the original source
+-- where the error came from, even if that's in another language.
+debug.getinfo = (thread,f,what)->
+    if what == nil
+        f,what,thread = thread,f,nil
+    if type(f) == 'number' then f += 1 -- Account for this wrapper function
+    info = if thread == nil
+        debug_getinfo(f,what)
+    else debug_getinfo(thread,f,what)
+    if not info or not info.func then return info
+    if info.short_src or info.source or info.linedefine or info.currentline
+        -- TODO: get name properly
+        if map = SOURCE_MAP[info.source]
+            if info.currentline
+                info.currentline = assert(map[info.currentline])
+            if info.linedefined
+                info.linedefined = assert(map[info.linedefined])
+            if info.lastlinedefined
+                info.lastlinedefined = assert(map[info.lastlinedefined])
+            info.short_src = info.source\match('@([^[]*)') or info.short_src
+    return info
+
+print_err_msg = (error_message, stack_offset=3)->
+    io.stderr\write("#{colored.red "ERROR:"} #{colored.bright colored.red (error_message or "")}\n")
+    io.stderr\write("stack traceback:\n")
+
+    -- TODO: properly print out the calling site of nomsu code, not just the *called* code
+    ok, to_lua = pcall -> require('moonscript.base').to_lua
+    if not ok then to_lua = -> nil
+    LINE_TABLES = setmetatable {},
+        __index: (file)=>
+            _, line_table = to_lua(file)
+            self[file] = line_table or false
+            return line_table or false
+
+    get_line = (file, line_no)->
+        start = LINE_STARTS[file][line_no] or 1
+        stop = (LINE_STARTS[file][line_no+1] or 0) - 1
+        return file\sub(start, stop)
+
+    level = stack_offset
+    while true
+        -- TODO: reduce duplicate code
+        calling_fn = debug_getinfo(level)
+        if not calling_fn then break
+        if calling_fn.func == run then break
+        level += 1
+        name = calling_fn.name and "function '#{calling_fn.name}'" or nil
+        if calling_fn.linedefined == 0 then name = "main chunk"
+        if name == "run_lua_fn" then continue
+        line = nil
+        if map = SOURCE_MAP[calling_fn.source]
+            if calling_fn.currentline
+                calling_fn.currentline = assert(map[calling_fn.currentline])
+            if calling_fn.linedefined
+                calling_fn.linedefined = assert(map[calling_fn.linedefined])
+            if calling_fn.lastlinedefined
+                calling_fn.lastlinedefined = assert(map[calling_fn.lastlinedefined])
+            --calling_fn.short_src = calling_fn.source\match('"([^[]*)')
+            filename,start,stop = calling_fn.source\match('@([^[]*)%[([0-9]+):([0-9]+)]')
+            assert(filename)
+            file = FILE_CACHE[filename]\sub(tonumber(start),tonumber(stop))
+            err_line = get_line(file, calling_fn.currentline)\sub(1,-2)
+            offending_statement = colored.bright(colored.red(err_line\match("^[ ]*(.*)")))
+            -- TODO: get name properly
+            name = "action '#{calling_fn.name}'"
+            line = colored.yellow("#{filename}:#{calling_fn.currentline} in #{name}\n        #{offending_statement}")
+        else
+            ok, file = pcall ->FILE_CACHE[calling_fn.short_src]
+            if not ok then file = nil
+            local line_num
+            if name == nil
+                search_level = level
+                _info = debug.getinfo(search_level)
+                while _info and (_info.func == pcall or _info.func == xpcall)
+                    search_level += 1
+                    _info = debug.getinfo(search_level)
+                if _info
+                    for i=1,999
+                        varname, val = debug.getlocal(search_level, i)
+                        if not varname then break
+                        if val == calling_fn.func
+                            name = "local '#{varname}'"
+                            if not varname\match("%(")
+                                break
+                    unless name
+                        for i=1,_info.nups
+                            varname, val = debug.getupvalue(_info.func, i)
+                            if not varname then break
+                            if val == calling_fn.func
+                                name = "upvalue '#{varname}'"
+                                if not varname\match("%(")
+                                    break
+            if file and calling_fn.short_src\match(".moon$") and LINE_TABLES[file]
+                char = LINE_TABLES[file][calling_fn.currentline]
+                line_num = 1
+                for _ in file\sub(1,char)\gmatch("\n") do line_num += 1
+                line = colored.cyan("#{calling_fn.short_src}:#{line_num} in #{name or '?'}")
+            else
+                line_num = calling_fn.currentline
+                if calling_fn.short_src == '[C]'
+                    line = colored.green("#{calling_fn.short_src} in #{name or '?'}")
+                else
+                    line = colored.blue("#{calling_fn.short_src}:#{calling_fn.currentline} in #{name or '?'}")
+
+            if file
+                err_line = get_line(file, line_num)\sub(1,-2)
+                offending_statement = colored.bright(colored.red(err_line\match("^[ ]*(.*)$")))
+                line ..= "\n        "..offending_statement
+        io.stderr\write("    #{line}\n")
+        if calling_fn.istailcall
+            io.stderr\write("    #{colored.dim colored.white "  (...tail calls...)"}\n")
+
+    io.stderr\flush!
+
+err_hand = (error_message)->
+    print_err_msg error_message
+    os.exit(false, true)
+
+-- Note: xpcall has a slightly different API in Lua <=5.1 vs. >=5.2, but this works
+-- for both APIs
+has_ldt, ldt = pcall(require,'ldt')
+safe_run = if has_ldt
+    ldt.guard
+else
+    (fn)->
+        xpcall(fn, err_hand)
+
+return safe_run

nomsu.lua

@@ -23,7 +23,6 @@ do
   local _obj_0 = string
   match, sub, rep, gsub, format, byte, match, find = _obj_0.match, _obj_0.sub, _obj_0.rep, _obj_0.gsub, _obj_0.format, _obj_0.byte, _obj_0.match, _obj_0.find
 end
-local debug_getinfo = debug.getinfo
 local NomsuCode, LuaCode, Source
 do
   local _obj_0 = require("code_obj")
@@ -32,6 +31,7 @@ end
 local AST = require("nomsu_tree")
 local parse = require("parser")
 local STDIN, STDOUT, STDERR = "/dev/fd/0", "/dev/fd/1", "/dev/fd/2"
+SOURCE_MAP = { }
 string.as_lua_id = function(str)
   local argnum = 0
   str = gsub(str, "x([0-9A-F][0-9A-F])", "x\0%1")
@@ -214,7 +214,6 @@ do
   NomsuCompiler.parse = function(self, ...)
     return parse(...)
   end
-  NomsuCompiler.source_map = { }
   local to_add = {
     repr = repr,
     stringify = stringify,
@@ -518,7 +517,7 @@ do
       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_key = tostring(source or lua.source)
-    if not (self.source_map[source_key]) then
+    if not (SOURCE_MAP[source_key]) then
       local map = { }
       local offset = 1
       source = source or lua.source
@@ -547,7 +546,7 @@ do
       fn(lua)
       map[lua_line] = map[lua_line] or nomsu_line
       map[0] = 0
-      self.source_map[source_key] = map
+      SOURCE_MAP[source_key] = map
     end
     return run_lua_fn()
   end
@@ -1148,7 +1147,7 @@ do
     end
   end
 end
-if arg and debug_getinfo(2).func ~= require then
+if arg and debug.getinfo(2).func ~= require then
   local parser = re.compile([[        args <- {| (flag ";")* {:inputs: {| ({file} ";")* |} :} {:nomsu_args: {| ("--;" ({[^;]*} ";")*)? |} :} ";"? |} !.
         flag <-
             {:interactive: ("-i" -> true) :}
@@ -1187,204 +1186,6 @@ OPTIONS
   end
   local nomsu = NomsuCompiler
   nomsu.arg = args.nomsu_args
-  local ok, to_lua = pcall(function()
-    return require('moonscript.base').to_lua
-  end)
-  if not ok then
-    to_lua = nil
-  end
-  local moonscript_line_tables = setmetatable({ }, {
-    __index = function(self, filename)
-      if not (to_lua) then
-        return nil
-      end
-      local _, line_table = to_lua(FILE_CACHE[filename])
-      self[filename] = line_table
-      return line_table
-    end
-  })
-  debug.getinfo = function(thread, f, what)
-    if what == nil then
-      f, what, thread = thread, f, nil
-    end
-    if type(f) == 'number' then
-      f = f + 1
-    end
-    local info
-    if thread == nil then
-      info = debug_getinfo(f, what)
-    else
-      info = debug_getinfo(thread, f, what)
-    end
-    if not info or not info.func then
-      return info
-    end
-    if info.short_src or info.source or info.linedefine or info.currentline then
-      do
-        local map = nomsu.source_map[info.source]
-        if map then
-          if info.currentline then
-            info.currentline = assert(map[info.currentline])
-          end
-          if info.linedefined then
-            info.linedefined = assert(map[info.linedefined])
-          end
-          if info.lastlinedefined then
-            info.lastlinedefined = assert(map[info.lastlinedefined])
-          end
-        end
-      end
-    end
-    return info
-  end
-  local print_err_msg
-  print_err_msg = function(error_message, stack_offset)
-    if stack_offset == nil then
-      stack_offset = 3
-    end
-    io.stderr:write(tostring(colored.red("ERROR:")) .. " " .. tostring(colored.bright(colored.red((error_message or "")))) .. "\n")
-    io.stderr:write("stack traceback:\n")
-    ok, to_lua = pcall(function()
-      return require('moonscript.base').to_lua
-    end)
-    if not ok then
-      to_lua = function()
-        return nil
-      end
-    end
-    local nomsu_source = FILE_CACHE["nomsu.moon"]
-    local LINE_TABLES = setmetatable({ }, {
-      __index = function(self, file)
-        local _, line_table = to_lua(file)
-        self[file] = line_table or false
-        return line_table or false
-      end
-    })
-    local get_line
-    get_line = function(file, line_no)
-      local start = LINE_STARTS[file][line_no] or 1
-      local stop = (LINE_STARTS[file][line_no + 1] or 0) - 1
-      return file:sub(start, stop)
-    end
-    local level = stack_offset
-    while true do
-      local _continue_0 = false
-      repeat
-        local calling_fn = debug_getinfo(level)
-        if not calling_fn then
-          break
-        end
-        if calling_fn.func == run then
-          break
-        end
-        level = level + 1
-        local name = calling_fn.name and "function '" .. tostring(calling_fn.name) .. "'" or nil
-        if calling_fn.linedefined == 0 then
-          name = "main chunk"
-        end
-        if name == "run_lua_fn" then
-          _continue_0 = true
-          break
-        end
-        local line = nil
-        do
-          local map = nomsu.source_map[calling_fn.source]
-          if map then
-            if calling_fn.currentline then
-              calling_fn.currentline = assert(map[calling_fn.currentline])
-            end
-            if calling_fn.linedefined then
-              calling_fn.linedefined = assert(map[calling_fn.linedefined])
-            end
-            if calling_fn.lastlinedefined then
-              calling_fn.lastlinedefined = assert(map[calling_fn.lastlinedefined])
-            end
-            local filename, start, stop = calling_fn.source:match('@([^[]*)%[([0-9]+):([0-9]+)]')
-            assert(filename)
-            local file = FILE_CACHE[filename]:sub(tonumber(start), tonumber(stop))
-            local err_line = get_line(file, calling_fn.currentline):sub(1, -2)
-            local offending_statement = colored.bright(colored.red(err_line:match("^[ ]*(.*)")))
-            name = "action '" .. tostring(calling_fn.name) .. "'"
-            line = colored.yellow(tostring(filename) .. ":" .. tostring(calling_fn.currentline) .. " in " .. tostring(name) .. "\n        " .. tostring(offending_statement))
-          else
-            local file
-            ok, file = pcall(function()
-              return FILE_CACHE[calling_fn.short_src]
-            end)
-            if not ok then
-              file = nil
-            end
-            local line_num
-            if name == nil then
-              local search_level = level
-              local _info = debug.getinfo(search_level)
-              while _info and (_info.func == pcall or _info.func == xpcall) do
-                search_level = search_level + 1
-                _info = debug.getinfo(search_level)
-              end
-              if _info then
-                for i = 1, 999 do
-                  local varname, val = debug.getlocal(search_level, i)
-                  if not varname then
-                    break
-                  end
-                  if val == calling_fn.func then
-                    name = "local '" .. tostring(varname) .. "'"
-                    if not varname:match("%(") then
-                      break
-                    end
-                  end
-                end
-                if not (name) then
-                  for i = 1, _info.nups do
-                    local varname, val = debug.getupvalue(_info.func, i)
-                    if not varname then
-                      break
-                    end
-                    if val == calling_fn.func then
-                      name = "upvalue '" .. tostring(varname) .. "'"
-                      if not varname:match("%(") then
-                        break
-                      end
-                    end
-                  end
-                end
-              end
-            end
-            if file and calling_fn.short_src:match(".moon$") and LINE_TABLES[file] then
-              local char = LINE_TABLES[file][calling_fn.currentline]
-              line_num = 1
-              for _ in file:sub(1, char):gmatch("\n") do
-                line_num = line_num + 1
-              end
-              line = colored.cyan(tostring(calling_fn.short_src) .. ":" .. tostring(line_num) .. " in " .. tostring(name or '?'))
-            else
-              line_num = calling_fn.currentline
-              if calling_fn.short_src == '[C]' then
-                line = colored.green(tostring(calling_fn.short_src) .. " in " .. tostring(name or '?'))
-              else
-                line = colored.blue(tostring(calling_fn.short_src) .. ":" .. tostring(calling_fn.currentline) .. " in " .. tostring(name or '?'))
-              end
-            end
-            if file then
-              local err_line = get_line(file, line_num):sub(1, -2)
-              local offending_statement = colored.bright(colored.red(err_line:match("^[ ]*(.*)$")))
-              line = line .. ("\n        " .. offending_statement)
-            end
-          end
-        end
-        io.stderr:write("    " .. tostring(line) .. "\n")
-        if calling_fn.istailcall then
-          io.stderr:write("    " .. tostring(colored.dim(colored.white("  (...tail calls...)"))) .. "\n")
-        end
-        _continue_0 = true
-      until true
-      if not _continue_0 then
-        break
-      end
-    end
-    return io.stderr:flush()
-  end
   local run
   run = function()
     for i, input in ipairs(args.inputs) do
@@ -1456,8 +1257,7 @@ OPTIONS
       local filename = input_files[_index_0]
       if args.syntax then
         local file_contents = io.open(filename):read('*a')
-        local err
+        local ok, err = pcall(nomsu.parse, nomsu, file_contents, Source(filename, 1, #file_contents))
-        ok, err = pcall(nomsu.parse, nomsu, file_contents, Source(filename, 1, #file_contents))
         if not ok then
           insert(parse_errs, err)
         elseif print_file then
@@ -1515,8 +1315,7 @@ OPTIONS
         err_hand = function(error_message)
           return print_err_msg(error_message)
         end
-        local ret
+        local ok, ret = xpcall(nomsu.run, err_hand, nomsu, buff, Source("REPL#" .. repl_line, 1, #buff))
-        ok, ret = xpcall(nomsu.run, err_hand, nomsu, buff, Source("REPL#" .. repl_line, 1, #buff))
         if ok and ret ~= nil then
           print("= " .. repr(ret))
         elseif not ok then
@@ -1525,19 +1324,7 @@ OPTIONS
       end
     end
   end
-  local err_hand
+  local run_safely = require("error_handling")
-  err_hand = function(error_message)
+  run_safely(run)
-    print_err_msg(error_message)
-    return os.exit(false, true)
-  end
-  do
-    local ldt
-    ok, ldt = pcall(require, 'ldt')
-    if ok then
-      ldt.guard(run)
-    else
-      xpcall(run, err_hand)
-    end
-  end
 end
 return NomsuCompiler

nomsu.moon

@@ -21,11 +21,14 @@ colored = setmetatable({}, {__index:(_,color)-> ((msg)-> colors[color]..tostring
 {:insert, :remove, :concat} = table
 unpack or= table.unpack
 {:match, :sub, :rep, :gsub, :format, :byte, :match, :find} = string
-debug_getinfo = debug.getinfo
 {:NomsuCode, :LuaCode, :Source} = require "code_obj"
 AST = require "nomsu_tree"
 parse = require("parser")
 STDIN, STDOUT, STDERR = "/dev/fd/0", "/dev/fd/1", "/dev/fd/2"
+-- Mapping from source string (e.g. "@core/metaprogramming.nom[1:100]") to a mapping
+-- from lua line number to nomsu line number
+export SOURCE_MAP
+SOURCE_MAP = {}
 
 string.as_lua_id = (str)->
     argnum = 0
@@ -147,9 +150,6 @@ with NomsuCompiler
     .nomsu = NomsuCompiler
     .parse = (...)=> parse(...)
 
-    -- Mapping from source string (e.g. "@core/metaprogramming.nom[1:100]") to a mapping
-    -- from lua line number to nomsu line number
-    .source_map = {}
     -- Discretionary/convenience stuff
     to_add = {
         repr:repr, stringify:stringify, utils:utils, lpeg:lpeg, re:re,
@@ -347,7 +347,7 @@ with NomsuCompiler
                 "\n")
             error("Failed to compile generated code:\n#{colored.bright colored.blue colored.onblack line_numbered_lua}\n\n#{err}", 0)
         source_key = tostring(source or lua.source)
-        unless @source_map[source_key]
+        unless SOURCE_MAP[source_key]
             map = {}
             offset = 1
             source or= lua.source
@@ -368,7 +368,7 @@ with NomsuCompiler
             map[lua_line] or= nomsu_line
             map[0] = 0
             -- Mapping from lua line number to nomsu line numbers
-            @source_map[source_key] = map
+            SOURCE_MAP[source_key] = map
 
         return run_lua_fn!
 
@@ -798,7 +798,7 @@ with NomsuCompiler
 
 -- Command line interface:
 -- Only run this code if this file was run directly with command line arguments, and not require()'d:
-if arg and debug_getinfo(2).func != require
+if arg and debug.getinfo(2).func != require
     parser = re.compile([[
         args <- {| (flag ";")* {:inputs: {| ({file} ";")* |} :} {:nomsu_args: {| ("--;" ({[^;]*} ";")*)? |} :} ";"? |} !.
         flag <-
@@ -836,130 +836,6 @@ OPTIONS
     nomsu = NomsuCompiler
     nomsu.arg = args.nomsu_args
     
-    ok, to_lua = pcall -> require('moonscript.base').to_lua
-    if not ok then to_lua = nil
-    moonscript_line_tables = setmetatable {}, {
-        __index: (filename)=>
-            return nil unless to_lua
-            _, line_table = to_lua(FILE_CACHE[filename])
-            self[filename] = line_table
-            return line_table
-    }
-
-    debug.getinfo = (thread,f,what)->
-        if what == nil
-            f,what,thread = thread,f,nil
-        if type(f) == 'number' then f += 1 -- Account for this wrapper function
-        info = if thread == nil
-            debug_getinfo(f,what)
-        else debug_getinfo(thread,f,what)
-        if not info or not info.func then return info
-        if info.short_src or info.source or info.linedefine or info.currentline
-            -- TODO: get name properly
-            if map = nomsu.source_map[info.source]
-                if info.currentline
-                    info.currentline = assert(map[info.currentline])
-                if info.linedefined
-                    info.linedefined = assert(map[info.linedefined])
-                if info.lastlinedefined
-                    info.lastlinedefined = assert(map[info.lastlinedefined])
-                --info.short_src = info.source\match('@([^[]*)')
-        return info
-
-    print_err_msg = (error_message, stack_offset=3)->
-        io.stderr\write("#{colored.red "ERROR:"} #{colored.bright colored.red (error_message or "")}\n")
-        io.stderr\write("stack traceback:\n")
-
-        -- TODO: properly print out the calling site of nomsu code, not just the *called* code
-        ok, to_lua = pcall -> require('moonscript.base').to_lua
-        if not ok then to_lua = -> nil
-        nomsu_source = FILE_CACHE["nomsu.moon"]
-        LINE_TABLES = setmetatable {},
-            __index: (file)=>
-                _, line_table = to_lua(file)
-                self[file] = line_table or false
-                return line_table or false
-
-        get_line = (file, line_no)->
-            start = LINE_STARTS[file][line_no] or 1
-            stop = (LINE_STARTS[file][line_no+1] or 0) - 1
-            return file\sub(start, stop)
-
-        level = stack_offset
-        while true
-            -- TODO: reduce duplicate code
-            calling_fn = debug_getinfo(level)
-            if not calling_fn then break
-            if calling_fn.func == run then break
-            level += 1
-            name = calling_fn.name and "function '#{calling_fn.name}'" or nil
-            if calling_fn.linedefined == 0 then name = "main chunk"
-            if name == "run_lua_fn" then continue
-            line = nil
-            if map = nomsu.source_map[calling_fn.source]
-                if calling_fn.currentline
-                    calling_fn.currentline = assert(map[calling_fn.currentline])
-                if calling_fn.linedefined
-                    calling_fn.linedefined = assert(map[calling_fn.linedefined])
-                if calling_fn.lastlinedefined
-                    calling_fn.lastlinedefined = assert(map[calling_fn.lastlinedefined])
-                --calling_fn.short_src = calling_fn.source\match('"([^[]*)')
-                filename,start,stop = calling_fn.source\match('@([^[]*)%[([0-9]+):([0-9]+)]')
-                assert(filename)
-                file = FILE_CACHE[filename]\sub(tonumber(start),tonumber(stop))
-                err_line = get_line(file, calling_fn.currentline)\sub(1,-2)
-                offending_statement = colored.bright(colored.red(err_line\match("^[ ]*(.*)")))
-                -- TODO: get name properly
-                name = "action '#{calling_fn.name}'"
-                line = colored.yellow("#{filename}:#{calling_fn.currentline} in #{name}\n        #{offending_statement}")
-            else
-                ok, file = pcall ->FILE_CACHE[calling_fn.short_src]
-                if not ok then file = nil
-                local line_num
-                if name == nil
-                    search_level = level
-                    _info = debug.getinfo(search_level)
-                    while _info and (_info.func == pcall or _info.func == xpcall)
-                        search_level += 1
-                        _info = debug.getinfo(search_level)
-                    if _info
-                        for i=1,999
-                            varname, val = debug.getlocal(search_level, i)
-                            if not varname then break
-                            if val == calling_fn.func
-                                name = "local '#{varname}'"
-                                if not varname\match("%(")
-                                    break
-                        unless name
-                            for i=1,_info.nups
-                                varname, val = debug.getupvalue(_info.func, i)
-                                if not varname then break
-                                if val == calling_fn.func
-                                    name = "upvalue '#{varname}'"
-                                    if not varname\match("%(")
-                                        break
-                if file and calling_fn.short_src\match(".moon$") and LINE_TABLES[file]
-                    char = LINE_TABLES[file][calling_fn.currentline]
-                    line_num = 1
-                    for _ in file\sub(1,char)\gmatch("\n") do line_num += 1
-                    line = colored.cyan("#{calling_fn.short_src}:#{line_num} in #{name or '?'}")
-                else
-                    line_num = calling_fn.currentline
-                    if calling_fn.short_src == '[C]'
-                        line = colored.green("#{calling_fn.short_src} in #{name or '?'}")
-                    else
-                        line = colored.blue("#{calling_fn.short_src}:#{calling_fn.currentline} in #{name or '?'}")
-
-                if file
-                    err_line = get_line(file, line_num)\sub(1,-2)
-                    offending_statement = colored.bright(colored.red(err_line\match("^[ ]*(.*)$")))
-                    line ..= "\n        "..offending_statement
-            io.stderr\write("    #{line}\n")
-            if calling_fn.istailcall
-                io.stderr\write("    #{colored.dim colored.white "  (...tail calls...)"}\n")
-
-        io.stderr\flush!
-    
     run = ->
     
         for i,input in ipairs args.inputs
@@ -1069,19 +945,7 @@ OPTIONS
                 elseif not ok
                     print_err_msg ret
     
-    err_hand = (error_message)->
+    run_safely = require "error_handling"
-        print_err_msg error_message
+    run_safely(run)
-        os.exit(false, true)
-
-    -- Note: xpcall has a slightly different API in Lua <=5.1 vs. >=5.2, but this works
-    -- for both APIs
-    -- TODO: revert back to old error handler
-
-    --require('ProFi')\profile "scratch/profile.txt", (profi)->
-    do
-        ok, ldt = pcall(require,'ldt')
-        if ok
-            ldt.guard run
-        else xpcall(run, err_hand)
 
 return NomsuCompiler

parser.moon

@@ -1,3 +1,4 @@
+-- This file contains the parser, which converts Nomsu text into abstract syntax trees
 lpeg = require 'lpeg'
 re = require 're'
 lpeg.setmaxstack 10000