Code cleanup.

Also modified the editing module's enclose() and select_enclosed() functions.

12 files changed, 263 insertions, 332 deletions

diff --git a/modules/lua/commands.lua b/modules/lua/commands.lua
index e8c11773..4857126c 100644
--- a/modules/lua/commands.lua
+++ b/modules/lua/commands.lua
@@ -124,7 +124,6 @@ function goto_required()
   end
   if not file then return end
   file = file:sub(2, -2):gsub('%.', '/')
-  local lfs = require 'lfs'
   for path in package.path:gmatch('[^;]+') do
     path = path:gsub('?', file)
     if lfs.attributes(path) then
@@ -137,6 +136,7 @@ end
 events.connect('file_before_save',
   function() -- show syntax errors as annotations
     if buffer:get_lexer() == 'lua' then
+      local buffer = buffer
       buffer:annotation_clear_all()
       local text = buffer:get_text()
       local _, err = loadstring(text)
@@ -169,7 +169,7 @@ local api_files = {
   ['view'] = _HOME..'/core/.view.luadoc',
 }
 -- Add API for loaded textadept modules.
-for p, _ in pairs(package.loaded) do
+for p in pairs(package.loaded) do
   if p:find('^_m%.textadept%.') then
     api_files[p] = _HOME..'/modules/textadept/'..p:match('[^%.]+$')..'.lua'
   end
@@ -181,11 +181,9 @@ for _, m in ipairs(lua) do
 end
 api_files[''] = _HOME..'/modules/lua/api/_G.luadoc'
 
-local lfs = require 'lfs'
-
 -- Load API.
 local apis = {}
-local current_doc = ''
+local current_doc = {}
 local f_args = {}
 for word, api_file in pairs(api_files) do
   if lfs.attributes(api_file) then
@@ -204,16 +202,17 @@ for word, api_file in pairs(api_files) do
         local funcs = apis[word].funcs
         funcs[#funcs + 1] = n..'?1'
         if f and #current_doc > 0 then
-          f = f..current_doc
-          current_doc = ''
+          table.insert(current_doc, 1, f)
+          f = table.concat(current_doc, '\n')
+          current_doc = {}
         end
         local c = line:find(':') and ':' or '.'
         if word == '' then c = '' end
         f_args[word..c..n] = f
       elseif line:match('^%-%-%-? (.+)$') then
-        current_doc = current_doc..'\n'..line:match('^%-%-%-? (.+)$')
+        current_doc[#current_doc + 1] = line:match('^%-%-%-? (.+)$')
       elseif #current_doc > 0 then
-        current_doc = ''
+        current_doc = {}
       end
     end
     table.sort(apis[word].fields)
@@ -229,6 +228,7 @@ local v_xpm = '/* XPM */\nstatic char *field[] = {\n/* columns rows colors chars
 -- @param pos Optional position to start from.
 -- @return word.
 local function prev_word(patt, pos)
+  local buffer = buffer
   local e = pos or buffer.current_pos - 1
   local s = e - 1
   while s >= 0 and string.char(buffer.char_at[s]):find(patt) do s = s - 1 end
@@ -240,6 +240,7 @@ end
 -- @param completions Table of completions.
 -- @see buffer:auto_c_show.
 local function auto_c_show(len, completions)
+  local buffer = buffer
   buffer:clear_registered_images()
   buffer:register_image(1, f_xpm)
   buffer:register_image(2, v_xpm)
@@ -267,6 +268,7 @@ if type(keys) == 'table' then
     },
     ['\n'] = { try_to_autocomplete_end },
     [not OSX and 'c\n' or 'esc'] = { function() -- complete API
+      local buffer = buffer
       local part = prev_word('[%w_]', buffer.current_pos)
       local pos = buffer.current_pos - #part - 1
       if pos > 0 then
diff --git a/modules/textadept/bookmarks.lua b/modules/textadept/bookmarks.lua
index 581390d4..bc5eac9b 100644
--- a/modules/textadept/bookmarks.lua
+++ b/modules/textadept/bookmarks.lua
@@ -49,10 +49,7 @@ end
 
 ---
 -- Clears all bookmarks in the current buffer.
-function clear()
-  local buffer = buffer
-  buffer:marker_delete_all(MARK_BOOKMARK)
-end
+function clear() buffer:marker_delete_all(MARK_BOOKMARK) end
 
 ---
 -- Goes to the next bookmark in the current buffer.
diff --git a/modules/textadept/command_entry.lua b/modules/textadept/command_entry.lua
index c18550e9..d8a48616 100644
--- a/modules/textadept/command_entry.lua
+++ b/modules/textadept/command_entry.lua
@@ -3,6 +3,9 @@
 
 local locale = _G.locale
 
+-- Environment for abbreviated commands.
+-- @class table
+-- @name env
 local env = setmetatable({}, {
   __index = function(t, k)
     local f = buffer[k]
@@ -46,37 +49,38 @@ events.connect('command_entry_keypress',
       local path, o, prefix = substring:match('^([%w_.:]-)([.:]?)([%w_]*)$')
       local f, err = loadstring('return ('..path..')')
       if type(f) == "function" then setfenv(f, env) end
-      local ret, tbl = pcall(f)
+      local ok, tbl = pcall(f)
       local cmpls = {}
-      if not ret then -- shorthand notation
+      prefix = '^'..prefix
+      if not ok then -- shorthand notation
         for _, t in ipairs{ buffer, view, gui, _G } do
           for k in pairs(t) do
-            if type(k) == 'string' and k:find('^'..prefix) then
+            if type(k) == 'string' and k:find(prefix) then
               cmpls[#cmpls + 1] = k
             end
           end
         end
         for f in pairs(_SCINTILLA.functions) do
-          if f:find('^'..prefix) then cmpls[#cmpls + 1] = f end
+          if f:find(prefix) then cmpls[#cmpls + 1] = f end
         end
         for p in pairs(_SCINTILLA.properties) do
-          if p:find('^'..prefix) then cmpls[#cmpls + 1] = p end
+          if p:find(prefix) then cmpls[#cmpls + 1] = p end
         end
       else
         if type(tbl) ~= 'table' then return end
         for k in pairs(tbl) do
-          if type(k) == 'string' and k:find('^'..prefix) then
+          if type(k) == 'string' and k:find(prefix) then
             cmpls[#cmpls + 1] = k
           end
         end
         if path == 'buffer' then
           if o == ':' then
             for f in pairs(_SCINTILLA.functions) do
-              if f:find('^'..prefix) then cmpls[#cmpls + 1] = f end
+              if f:find(prefix) then cmpls[#cmpls + 1] = f end
             end
           else
             for p in pairs(_SCINTILLA.properties) do
-              if p:find('^'..prefix) then cmpls[#cmpls + 1] = p end
+              if p:find(prefix) then cmpls[#cmpls + 1] = p end
             end
           end
         end
diff --git a/modules/textadept/editing.lua b/modules/textadept/editing.lua
index c2b06ba0..12c72d05 100644
--- a/modules/textadept/editing.lua
+++ b/modules/textadept/editing.lua
@@ -52,28 +52,10 @@ INDIC_HIGHLIGHT_ALPHA = 100
 -- @see block_comment
 comment_string = {}
 
----
--- Enclosures for enclosing or selecting ranges of text.
--- Note chars and tag enclosures are generated at runtime.
--- You can add entries to the table in language-specific modules and use the
--- 'enclose' function in key commands.
--- @class table
--- @name enclosure
--- @see enclose
-enclosure = {
-  dbl_quotes = { left = '"', right = '"' },
-  sng_quotes = { left = "'", right = "'" },
-  parens     = { left = '(', right = ')' },
-  brackets   = { left = '[', right = ']' },
-  braces     = { left = '{', right = '}' },
-  chars      = { left = ' ', right = ' ' },
-  tags       = { left = '>', right = '<' },
-  tag        = { left = ' ', right = ' ' },
-  single_tag = { left = '<', right = ' />' }
-}
-
 -- Character matching.
 -- Used for auto-matching parentheses, brackets, braces, and quotes.
+-- @class table
+-- @name char_matches
 local char_matches = {
   [40] = ')', [91] = ']', [123] = '}',
   [39] = "'", [34] = '"'
@@ -81,6 +63,8 @@ local char_matches = {
 
 -- Brace characters.
 -- Used for going to matching brace positions.
+-- @class table
+-- @name braces
 local braces = { -- () [] {} <>
   [40] = 1, [91] = 1, [123] = 1, [60] = 1,
   [41] = 1, [93] = 1, [125] = 1, [62] = 1,
@@ -88,6 +72,8 @@ local braces = { -- () [] {} <>
 
 -- The current call tip.
 -- Used for displaying call tips.
+-- @class table
+-- @name current_call_tip
 local current_call_tip = {}
 
 events.connect('char_added',
@@ -99,21 +85,20 @@ events.connect('char_added',
 
 events.connect('keypress',
   function(code, shift, control, alt) -- removes matched chars on backspace
-    if AUTOPAIR and code == 0xff08 and buffer.selections == 1 then
-      local buffer = buffer
-      local current_pos = buffer.current_pos
-      local c = buffer.char_at[current_pos - 1]
-      if char_matches[c] and
-        buffer.char_at[current_pos] == string.byte(char_matches[c]) then
-        buffer:clear()
-      end
+    if not AUTOPAIR or code ~= 0xff08 or buffer.selections ~= 1 then return end
+    local buffer = buffer
+    local current_pos = buffer.current_pos
+    local c = buffer.char_at[current_pos - 1]
+    if char_matches[c] and
+      buffer.char_at[current_pos] == string.byte(char_matches[c]) then
+      buffer:clear()
     end
   end)
 
 events.connect('update_ui',
   function() -- highlights matching braces
-    local buffer = buffer
     if not HIGHLIGHT_BRACES then return end
+    local buffer = buffer
     local current_pos = buffer.current_pos
     if braces[buffer.char_at[current_pos]] and
       buffer:get_style_name(buffer.style_at[current_pos]) == 'operator' then
@@ -133,16 +118,14 @@ events.connect('char_added',
     if not AUTOINDENT or char ~= 10 then return end
     local buffer = buffer
     local anchor, caret = buffer.anchor, buffer.current_pos
-    local curr_line = buffer:line_from_position(caret)
-    local last_line = curr_line - 1
-    while last_line >= 0 and #buffer:get_line(last_line) == 1 do
-      last_line = last_line - 1
-    end
-    if last_line >= 0 then
-      local indentation = buffer.line_indentation[last_line]
-      local s = buffer.line_indent_position[curr_line]
-      buffer.line_indentation[curr_line] = indentation
-      local e = buffer.line_indent_position[curr_line]
+    local line = buffer:line_from_position(caret)
+    local pline = line - 1
+    while pline >= 0 and #buffer:get_line(pline) == 1 do pline = pline - 1 end
+    if pline >= 0 then
+      local indentation = buffer.line_indentation[pline]
+      local s = buffer.line_indent_position[line]
+      buffer.line_indentation[line] = indentation
+      local e = buffer.line_indent_position[line]
       local diff = e - s
       if e > s then -- move selection on
         if anchor >= s then anchor = anchor + diff end
@@ -179,6 +162,7 @@ end
 -- Pops up an autocompletion list for the current word based on other words in
 -- the document.
 -- @param word_chars String of chars considered to be part of words.
+-- @return true if there were completions to show; false otherwise.
 function autocomplete_word(word_chars)
   local buffer = buffer
   local caret, length = buffer.current_pos, buffer.length
@@ -241,7 +225,6 @@ end
 -- Goes to the requested line.
 -- @param line Optional line number to go to.
 function goto_line(line)
-  local buffer = buffer
   if not line then
     line = gui.dialog('standard-inputbox',
                       '--title', L('Go To'),
@@ -259,8 +242,8 @@ end
 -- Strips trailing whitespace off of every line, ensures an ending newline, and
 -- converts non-consistent EOLs.
 function prepare_for_save()
-  local buffer = buffer
   if not SAVE_STRIPS_WS then return end
+  local buffer = buffer
   buffer:begin_undo_action()
   -- Strip trailing whitespace.
   local lines = buffer.line_count
@@ -304,27 +287,21 @@ end
 
 ---
 -- Transposes characters intelligently.
--- If the caret is at the end of the current word, the two characters before
--- the caret are transposed. Otherwise the characters to the left and right of
--- the caret are transposed.
+-- If the caret is at the end of a line, the two characters before the caret are
+-- transposed. Otherwise, the characters to the left and right are.
 function transpose_chars()
   local buffer = buffer
   buffer:begin_undo_action()
-  local caret = buffer.current_pos
-  local char = buffer.char_at[caret - 1]
+  local pos = buffer.current_pos
+  local c1, c2 = buffer.char_at[pos - 1], buffer.char_at[pos]
   buffer:delete_back()
-  if caret > buffer.length or buffer.char_at[caret - 1] == 32 then
-    buffer:char_left()
-  else
-    buffer:char_right()
-  end
-  buffer:insert_text(-1, string.char(char))
+  buffer:insert_text((c2 == 10 or c2 == 13) and pos - 2 or pos, string.char(c1))
   buffer:end_undo_action()
-  buffer:goto_pos(caret)
+  buffer:goto_pos(pos)
 end
 
 ---
--- Joins the current line with the line below, eliminating whitespace.
+-- Joins the current line with the line below.
 function join_lines()
   local buffer = buffer
   buffer:line_end()
@@ -334,77 +311,33 @@ function join_lines()
   buffer:lines_join()
 end
 
--- Returns the number to the left of the caret.
--- This is used for the enclose function.
--- @see enclose
-local function get_preceding_number()
-  local buffer = buffer
-  local caret = buffer.current_pos
-  local char = buffer.char_at[caret - 1]
-  local txt = ''
-  while tonumber(string.char(char)) do
-    txt = txt..string.char(char)
-    caret = caret - 1
-    char = buffer.char_at[caret - 1]
-  end
-  return tonumber(txt) or 1, #txt
-end
-
 ---
--- Encloses text in an enclosure set.
+-- Encloses text within a given pair of strings.
 -- If text is selected, it is enclosed. Otherwise, the previous word is
--- enclosed. The n previous words can be enclosed by appending n (a number) to
--- the end of the last word. When enclosing with a character, append the
--- character to the end of the word(s). To enclose previous word(s) with n
--- characters, append n (a number) to the end of character set.
--- Examples:
---   enclose this2 -> 'enclose this' (enclose in sng_quotes)
---   enclose this2**2 -> **enclose this**
--- @param str The enclosure type in enclosure.
--- @see enclosure
--- @see get_preceding_number
-function enclose(str)
+-- enclosed.
+-- @param left The left part of the enclosure.
+-- @param right The right part of the enclosure.
+function enclose(left, right)
   local buffer = buffer
   buffer:begin_undo_action()
   local txt = buffer:get_sel_text()
-  if txt == '' then
-    if str == 'chars' then
-      local num_chars, len_num_chars = get_preceding_number()
-      for i = 1, len_num_chars do buffer:delete_back() end
-      for i = 1, num_chars do buffer:char_left_extend() end
-      enclosure[str].left  = buffer:get_sel_text()
-      enclosure[str].right = enclosure[str].left
-      buffer:delete_back()
-    end
-    local num_words, len_num_chars = get_preceding_number()
-    for i = 1, len_num_chars do buffer:delete_back() end
-    for i = 1, num_words do buffer:word_left_extend() end
+  if #txt == 0 then
+    buffer:word_left_extend()
     txt = buffer:get_sel_text()
   end
-  local len = 0
-  if str == 'tag' then
-    enclosure[str].left  = '<'..txt..'>'
-    enclosure[str].right = '</'..txt..'>'
-    len = #txt + 3
-    txt = ''
-  end
-  local left  = enclosure[str].left
-  local right = enclosure[str].right
   buffer:replace_sel(left..txt..right)
-  if str == 'tag' then buffer:goto_pos(buffer.current_pos - len) end
   buffer:end_undo_action()
 end
 
 ---
--- Selects text in a specified enclosure.
--- @param str The enclosure type in enclosure.
--- @see enclosure
-function select_enclosed(str)
-  if not str then return end
+-- Selects text between a given pair of strings.
+-- @param left The left part of the enclosure.
+-- @param right The right part of the enclosure.
+function select_enclosed(left, right)
   local buffer = buffer
   buffer:search_anchor()
-  local s = buffer:search_prev(0, enclosure[str].left)
-  local e = buffer:search_next(0, enclosure[str].right)
+  local s = buffer:search_prev(0, left)
+  local e = buffer:search_next(0, right)
   if s and e then buffer:set_sel(s + 1, e) end
 end
 
@@ -424,7 +357,6 @@ end
 ---
 -- Selects the current line.
 function select_line()
-  local buffer = buffer
   buffer:home()
   buffer:line_end_extend()
 end
@@ -433,7 +365,6 @@ end
 -- Selects the current paragraph.
 -- Paragraphs are delimited by two or more consecutive newlines.
 function select_paragraph()
-  local buffer = buffer
   buffer:para_up()
   buffer:para_down_extend()
 end
@@ -467,7 +398,7 @@ function select_indented_block()
 end
 
 ---
--- Selects all text with the same scope/style as under the caret.
+-- Selects all text with the same style as under the caret.
 function select_scope()
   local buffer = buffer
   local start_pos = buffer.current_pos
diff --git a/modules/textadept/find.lua b/modules/textadept/find.lua
index db34358c..202f7b49 100644
--- a/modules/textadept/find.lua
+++ b/modules/textadept/find.lua
@@ -4,19 +4,19 @@ local L = _G.locale.localize
 local events = _G.events
 local find = gui.find
 
-local lfs = require 'lfs'
-
 local MARK_FIND = 0
 local MARK_FIND_COLOR = 0x4D9999
 local previous_view
 
 -- Text escape sequences with their associated characters.
+-- @class table
+-- @name escapes
 local escapes = {
   ['\\a'] = '\a', ['\\b'] = '\b', ['\\f'] = '\f', ['\\n'] = '\n',
   ['\\r'] = '\r', ['\\t'] = '\t', ['\\v'] = '\v', ['\\\\'] = '\\'
 }
 
--- LuaDoc is in core/.find.luadoc
+-- LuaDoc is in core/.find.luadoc.
 function find.find_in_files(utf8_dir)
   if not utf8_dir then
     utf8_dir = gui.dialog('fileselect',
@@ -26,13 +26,12 @@ function find.find_in_files(utf8_dir)
                           (buffer.filename or ''):match('^.+[/\\]') or '',
                           '--no-newline')
   end
-  local text = find.find_entry_text
   if #utf8_dir > 0 then
+    local text = find.find_entry_text
     if not find.lua then text = text:gsub('([().*+?^$%%[%]-])', '%%%1') end
     if not find.match_case then text = text:lower() end
     if find.whole_word then text = '[^%W_]'..text..'[^%W_]' end
-    local match_case = find.match_case
-    local whole_word = find.whole_word
+    local match_case, whole_word = find.match_case, find.whole_word
     local string_find, format = string.find, string.format
     local matches = { 'Find: '..text }
     function search_file(file)
@@ -48,11 +47,12 @@ function find.find_in_files(utf8_dir)
         line_num = line_num + 1
       end
     end
+    local lfs_dir, lfs_attributes = lfs.dir, lfs.attributes
     function search_dir(directory)
-      for file in lfs.dir(directory) do
+      for file in lfs_dir(directory) do
         if not file:find('^%.%.?$') then -- ignore . and ..
           local path = directory..'/'..file
-          local type = lfs.attributes(path).mode
+          local type = lfs_attributes(path).mode
           if type == 'directory' then
             search_dir(path)
           elseif type == 'file' then
@@ -108,11 +108,7 @@ local function find_(text, next, flags, nowrap, wrapped)
   if flags < 8 then
     buffer:goto_pos(buffer[next and 'current_pos' or 'anchor'] + increment)
     buffer:search_anchor()
-    if next then
-      result = buffer:search_next(flags, text)
-    else
-      result = buffer:search_prev(flags, text)
-    end
+    result = buffer['search_'..(next and 'next' or 'prev')](buffer, flags, text)
     if result ~= -1 then buffer:scroll_caret() end
 
   elseif flags < 16 then -- lua pattern search (forward search only)
@@ -128,17 +124,13 @@ local function find_(text, next, flags, nowrap, wrapped)
     end
 
   else -- find in files
-    find_in_files()
+    find.find_in_files()
     return
   end
 
   if result == -1 and not nowrap and not wrapped then -- wrap the search
     local anchor, pos = buffer.anchor, buffer.current_pos
-    if next or flags >= 8 then
-      buffer:goto_pos(0)
-    else
-      buffer:goto_pos(buffer.length)
-    end
+    buffer:goto_pos((next or flags >= 8) and 0 or buffer.length)
     gui.statusbar_text = L('Search wrapped')
     result = find_(text, next, flags, true, true)
     if result == -1 then
@@ -162,12 +154,11 @@ events.connect('find', find_)
 local function find_incremental(text)
   local c = _SCINTILLA.constants
   local flags = find.match_case and c.SCFIND_MATCHCASE or 0
-  --if find.lua then flags = flags + 8 end
   buffer:goto_pos(find.incremental_start or 0)
   find_(text, true, flags)
 end
 
--- LuaDoc is in core/.find.lua.
+-- LuaDoc is in core/.find.luadoc.
 function find.find_incremental()
   find.incremental = true
   find.incremental_start = buffer.current_pos
@@ -220,10 +211,10 @@ local function replace(rtext)
       rtext = rtext:gsub('%%'..i, v)
     end
   end
-  local ret, rtext = pcall(rtext.gsub, rtext, '%%(%b())',
+  local ok, rtext = pcall(rtext.gsub, rtext, '%%(%b())',
     function(code)
-      local ret, val = pcall(loadstring('return '..code))
-      if not ret then
+      local ok, val = pcall(loadstring('return '..code))
+      if not ok then
         gui.dialog('ok-msgbox',
                    '--title', L('Error'),
                    '--text', L('An error occured:'),
@@ -233,7 +224,7 @@ local function replace(rtext)
       end
       return val
     end)
-  if ret then
+  if ok then
     rtext = rtext:gsub('\\037', '%%') -- unescape '%'
     buffer:replace_target(rtext:gsub('\\[abfnrtv\\]', escapes))
     buffer:goto_pos(buffer.target_end) -- 'find' text after this replacement
@@ -287,8 +278,7 @@ local function replace_all(ftext, rtext, flags)
     buffer:set_sel(anchor, current_pos)
     buffer:marker_delete_handle(end_marker)
   end
-  gui.statusbar_text = string.format("%d %s", tostring(count),
-                                     L('replacement(s) made'))
+  gui.statusbar_text = string.format("%d %s", count, L('replacement(s) made'))
   buffer:end_undo_action()
 end
 events.connect('replace_all', replace_all)
@@ -312,8 +302,8 @@ local function goto_file(pos, line_num)
         local clicked_view = view
         if previous_view then previous_view:focus() end
         if buffer._type == L('[Files Found Buffer]') then
-          -- there are at least two find in files views; find one of those views
-          -- that the file was not selected from and focus it
+          -- There are at least two find in files views; find one of those views
+          -- that the file was not selected from and focus it.
           for _, v in ipairs(_VIEWS) do
             if v ~= clicked_view then
               previous_view = v
@@ -331,7 +321,7 @@ local function goto_file(pos, line_num)
 end
 events.connect('double_click', goto_file)
 
--- LuaDoc is in core/.find.lua.
+-- LuaDoc is in core/.find.luadoc.
 function find.goto_file_in_list(next)
   local orig_view = view
   for _, buffer in ipairs(_BUFFERS) do
diff --git a/modules/textadept/keys.lua b/modules/textadept/keys.lua
index 67512b51..ad4ed760 100644
--- a/modules/textadept/keys.lua
+++ b/modules/textadept/keys.lua
@@ -87,18 +87,18 @@ module('_m.textadept.keys', package.seeall)
 --       ['ctrl+b'] = { 'char_left',  'buffer' },
 --       lua = {
 --         ['ctrl+c'] = { 'add_text', 'buffer', '-- ' },
---         whitespace = {
---           ['ctrl+f'] = { function() print('whitespace') end }
+--         comment = {
+--           ['ctrl+f'] = { function() print('comment') end }
 --         }
 --       }
 --     }
 --
 -- The first two key commands are global and call `buffer:char_right()` and
 -- `buffer:char_left()` respectively. The last two commands apply only in the
--- Lua lexer with the very last one only being available in Lua's `whitespace`
--- style. If `ctrl+f` is pressed when the current style is `whitespace` in the
+-- Lua lexer with the very last one only being available in Lua's `comment`
+-- style. If `ctrl+f` is pressed when the current style is `comment` in the
 -- `lua` lexer, the global key command with the same shortcut is overridden and
--- `whitespace` is printed to standard out.
+-- `comment` is printed to standard out.
 --
 -- ## Problems
 --
@@ -114,6 +114,20 @@ module('_m.textadept.keys', package.seeall)
 
 -- Windows and Linux key commands are listed in the first block.
 -- Mac OSX key commands are listed in the second block.
+--
+-- ## Events
+--
+-- The following is a list of all key events generated in
+-- `event_name(arguments)` format:
+--
+-- * **keypress** (code, shift, control, alt)<br />
+--   Called when a key is pressed.
+--       - code: the key code (according to `<gdk/gdkkeysyms.h>`).
+--       - shift: flag indicating whether or not the Shift key is pressed.
+--       - control: flag indicating whether or not the Control key is pressed.
+--       - alt: flag indicating whether or not the Alt/Apple key is pressed.
+--   <br />
+--   Note: The Alt-Option key in Mac OSX is not available.
 
 -- settings
 local SCOPES_ENABLED = true
@@ -127,6 +141,46 @@ local keys = _M
 local b, v = 'buffer', 'view'
 local gui = gui
 
+-- Utility functions used by both layouts.
+local function enclose_in_tag()
+  m_editing.enclose('<', '>')
+  local buffer = buffer
+  local pos = buffer.current_pos
+  while buffer.char_at[pos - 1] ~= 60 do pos = pos - 1 end -- '<'
+  buffer:insert_text(-1, '</'..buffer:text_range(pos, buffer.current_pos))
+end
+local function any_char_mt(f)
+  return setmetatable({['\0'] = {}}, {
+                        __index = function(t, k)
+                          if #k == 1 then return { f, k, k } end
+                        end })
+end
+local function toggle_setting(setting)
+  local state = buffer[setting]
+  if type(state) == 'boolean' then
+    buffer[setting] = not state
+  elseif type(state) == 'number' then
+    buffer[setting] = buffer[setting] == 0 and 1 or 0
+  end
+  events.emit('update_ui') -- for updating statusbar
+end
+local RECENT_FILES = 1
+events.connect('user_list_selection',
+  function(type, text)
+    if type == RECENT_FILES then io.open_file(text) end
+  end)
+local function show_recent_file_list()
+  local buffer = buffer
+  local files = {}
+  for _, filename in ipairs(io.recent_files) do
+    table.insert(files, 1, filename)
+  end
+  local sep = buffer.auto_c_separator
+  buffer.auto_c_separator = ('|'):byte()
+  buffer:user_list_show(RECENT_FILES, table.concat(files, '|'))
+  buffer.auto_c_separator = sep
+end
+
 -- CTRL = 'c'
 -- SHIFT = 's'
 -- ALT = 'a'
@@ -172,38 +226,39 @@ if not OSX then
   keys.cv = { 'paste', b      }
   -- Delete is delete.
   keys.ca = { 'select_all', b }
-  keys.ce     = { m_editing.match_brace              }
-  keys.cE     = { m_editing.match_brace, 'select'    }
-  keys['c\n'] = { m_editing.autocomplete_word, '%w_' }
+  keys.ce       = { m_editing.match_brace              }
+  keys.cE       = { m_editing.match_brace, 'select'    }
+  keys['c\n']   = { m_editing.autocomplete_word, '%w_' }
   keys['c\n\r'] = { m_editing.autocomplete_word, '%w_' } -- win32
-  keys.cq     = { m_editing.block_comment            }
+  keys.cq       = { m_editing.block_comment            }
   -- TODO: { m_editing.current_word, 'delete' }
   keys.ch = { m_editing.highlight_word }
   -- TODO: { m_editing.transpose_chars }
   -- TODO: { m_editing.convert_indentation }
   keys.ac = { -- enClose in...
-    t     = { m_editing.enclose, 'tag'        },
-    T     = { m_editing.enclose, 'single_tag' },
-    ['"'] = { m_editing.enclose, 'dbl_quotes' },
-    ["'"] = { m_editing.enclose, 'sng_quotes' },
-    ['('] = { m_editing.enclose, 'parens'     },
-    ['['] = { m_editing.enclose, 'brackets'   },
-    ['{'] = { m_editing.enclose, 'braces'     },
-    c     = { m_editing.enclose, 'chars'      },
+    t     = { enclose_in_tag },
+    T     = { m_editing.enclose, '<', ' />' },
+    ['"'] = { m_editing.enclose, '"', '"'   },
+    ["'"] = { m_editing.enclose, "'", "'"   },
+    ['('] = { m_editing.enclose, '(', ')'   },
+    ['['] = { m_editing.enclose, '[', ']'   },
+    ['{'] = { m_editing.enclose, '{', '}'   },
+    c     = any_char_mt(m_editing.enclose),
   }
   keys.as = { -- select in...
-    t     = { m_editing.select_enclosed, 'tags'       },
-    ['"'] = { m_editing.select_enclosed, 'dbl_quotes' },
-    ["'"] = { m_editing.select_enclosed, 'sng_quotes' },
-    ['('] = { m_editing.select_enclosed, 'parens'     },
-    ['['] = { m_editing.select_enclosed, 'brackets'   },
-    ['{'] = { m_editing.select_enclosed, 'braces'     },
-    w     = { m_editing.current_word, 'select'        },
-    l      = { m_editing.select_line                   },
-    p      = { m_editing.select_paragraph              },
-    b      = { m_editing.select_indented_block         },
-    s      = { m_editing.select_scope                  },
-    g      = { m_editing.grow_selection, 1             },
+    t     = { m_editing.select_enclosed, '>', '<' },
+    ['"'] = { m_editing.select_enclosed, '"', '"' },
+    ["'"] = { m_editing.select_enclosed, "'", "'" },
+    ['('] = { m_editing.select_enclosed, '(', ')' },
+    ['['] = { m_editing.select_enclosed, '[', ']' },
+    ['{'] = { m_editing.select_enclosed, '{', '}' },
+    w     = { m_editing.current_word, 'select'    },
+    l     = { m_editing.select_line               },
+    p     = { m_editing.select_paragraph          },
+    b     = { m_editing.select_indented_block     },
+    s     = { m_editing.select_scope              },
+    g     = { m_editing.grow_selection, 1         },
+    c     = any_char_mt(m_editing.select_enclosed),
   }
 
   -- Search
@@ -236,15 +291,6 @@ if not OSX then
   keys.cb      = { gui.switch_buffer           }
   keys['c\t']  = { 'goto_buffer', v, 1, false  }
   keys['cs\t'] = { 'goto_buffer', v, -1, false }
-  local function toggle_setting(setting)
-    local state = buffer[setting]
-    if type(state) == 'boolean' then
-      buffer[setting] = not state
-    elseif type(state) == 'number' then
-      buffer[setting] = buffer[setting] == 0 and 1 or 0
-    end
-    events.emit('update_ui') -- for updating statusbar
-  end
   keys.ct.v = {
     e      = { toggle_setting, 'view_eol'           },
     w      = { toggle_setting, 'wrap_mode'          },
@@ -269,25 +315,7 @@ if not OSX then
   keys.c0 = { function() buffer.zoom = 0 end }
 
   -- Miscellaneous not in standard menu.
-  -- Recent files.
-  local RECENT_FILES = 1
-  events.connect('user_list_selection',
-    function(type, text)
-      if type == RECENT_FILES then io.open_file(text) end
-    end)
-  keys.ao = {
-    function()
-      local buffer = buffer
-      local files = {}
-      for _, filename in ipairs(io.recent_files) do
-        table.insert(files, 1, filename)
-      end
-      local sep = buffer.auto_c_separator
-      buffer.auto_c_separator = ('|'):byte()
-      buffer:user_list_show(RECENT_FILES, table.concat(files, '|'))
-      buffer.auto_c_separator = sep
-    end
-  }
+  keys.ao = { show_recent_file_list }
 
 else
   -- Mac OSX key commands
@@ -336,36 +364,36 @@ else
   keys.ct = { m_editing.transpose_chars }
   -- TODO: { m_editing.convert_indentation }
   keys.cc = { -- enClose in...
-    t     = { m_editing.enclose, 'tag'        },
-    T     = { m_editing.enclose, 'single_tag' },
-    ['"'] = { m_editing.enclose, 'dbl_quotes' },
-    ["'"] = { m_editing.enclose, 'sng_quotes' },
-    ['('] = { m_editing.enclose, 'parens'     },
-    ['['] = { m_editing.enclose, 'brackets'   },
-    ['{'] = { m_editing.enclose, 'braces'     },
-    c     = { m_editing.enclose, 'chars'      },
+    t     = { enclose_in_tag },
+    T     = { m_editing.enclose, '<', ' />' },
+    ['"'] = { m_editing.enclose, '"', '"'   },
+    ["'"] = { m_editing.enclose, "'", "'"   },
+    ['('] = { m_editing.enclose, '(', ')'   },
+    ['['] = { m_editing.enclose, '[', ']'   },
+    ['{'] = { m_editing.enclose, '{', '}'   },
+    c     = any_char_mt(m_editing.enclose),
   }
   keys.cs = { -- select in...
-    e     = { m_editing.select_enclosed               },
-    t     = { m_editing.select_enclosed, 'tags'       },
-    ['"'] = { m_editing.select_enclosed, 'dbl_quotes' },
-    ["'"] = { m_editing.select_enclosed, 'sng_quotes' },
-    ['('] = { m_editing.select_enclosed, 'parens'     },
-    ['['] = { m_editing.select_enclosed, 'brackets'   },
-    ['{'] = { m_editing.select_enclosed, 'braces'     },
-    w     = { m_editing.current_word, 'select'        },
-    l     = { m_editing.select_line                   },
-    p     = { m_editing.select_paragraph              },
-    b     = { m_editing.select_indented_block         },
-    s     = { m_editing.select_scope                  },
-    g     = { m_editing.grow_selection, 1             },
+    t     = { m_editing.select_enclosed, '>', '<' },
+    ['"'] = { m_editing.select_enclosed, '"', '"' },
+    ["'"] = { m_editing.select_enclosed, "'", "'" },
+    ['('] = { m_editing.select_enclosed, '(', ')' },
+    ['['] = { m_editing.select_enclosed, '[', ']' },
+    ['{'] = { m_editing.select_enclosed, '{', '}' },
+    w     = { m_editing.current_word, 'select'    },
+    l     = { m_editing.select_line               },
+    p     = { m_editing.select_paragraph          },
+    b     = { m_editing.select_indented_block     },
+    s     = { m_editing.select_scope              },
+    g     = { m_editing.grow_selection, 1         },
+    c     = any_char_mt(m_editing.select_enclosed),
   }
 
   -- Search
-  keys.af = { gui.find.focus       } -- find/replace
-  keys.ag = { gui.find.find_next   }
-  keys.aG = { gui.find.find_prev   }
-  keys.ar = { gui.find.replace     }
+  keys.af = { gui.find.focus     } -- find/replace
+  keys.ag = { gui.find.find_next }
+  keys.aG = { gui.find.find_prev }
+  keys.ar = { gui.find.replace   }
   keys.ai = { gui.find.find_incremental }
   keys.aF = {
     function()
@@ -375,7 +403,7 @@ else
   }
   keys.cag = { gui.find.goto_file_in_list, true  }
   keys.caG = { gui.find.goto_file_in_list, false }
-  keys.cg  = { m_editing.goto_line             }
+  keys.cg  = { m_editing.goto_line               }
 
   -- Tools
   keys['f2'] = { gui.command_entry.focus }
@@ -395,15 +423,6 @@ else
   keys.ab      = { gui.switch_buffer           }
   keys['c\t']  = { 'goto_buffer', v, 1, false  }
   keys['cs\t'] = { 'goto_buffer', v, -1, false }
-  local function toggle_setting(setting)
-    local state = buffer[setting]
-    if type(state) == 'boolean' then
-      buffer[setting] = not state
-    elseif type(state) == 'number' then
-      buffer[setting] = buffer[setting] == 0 and 1 or 0
-    end
-    events.emit('update_ui') -- for updating statusbar
-  end
   keys.at.v = {
     e      = { toggle_setting, 'view_eol'           },
     w      = { toggle_setting, 'wrap_mode'          },
@@ -428,25 +447,7 @@ else
   keys.c0 = { function() buffer.zoom = 0 end }
 
   -- Miscellaneous not in standard menu.
-  -- Recent files.
-  local RECENT_FILES = 1
-  events.connect('user_list_selection',
-    function(type, text)
-      if type == RECENT_FILES then io.open_file(text) end
-    end)
-  keys.co = {
-    function()
-      local buffer = buffer
-      local files = {}
-      for _, filename in ipairs(io.recent_files) do
-        table.insert(files, 1, filename)
-      end
-      local sep = buffer.auto_c_separator
-      buffer.auto_c_separator = ('|'):byte()
-      buffer:user_list_show(RECENT_FILES, table.concat(files, '|'))
-      buffer.auto_c_separator = sep
-    end
-  }
+  keys.co = { show_recent_file_list }
 
   -- Movement/selection commands
   keys.cf  = { 'char_right',        b }
@@ -469,7 +470,7 @@ else
   keys.cah = { 'del_word_left',     b }
   keys.cd  = { 'clear',             b }
   keys.cad = { 'del_word_right',    b }
-  keys.ck = {
+  keys.ck  = {
     function()
       buffer:line_end_extend()
       buffer:cut()
@@ -568,9 +569,7 @@ local function run_key_command(lexer, scope)
     end
   end
 
-  if type(f) ~= 'function' then
-    error(L('Unknown command:')..tostring(f))
-  end
+  if type(f) ~= 'function' then error(L('Unknown command:')..tostring(f)) end
   return f(unpack(args)) == false and PROPAGATE or HALT
 end
 
@@ -594,19 +593,9 @@ local function keypress(code, shift, control, alt)
   if code < 256 then
     key = string_char(code)
     shift = false -- for printable characters, key is upper case
-    if OSX and not shift and not control and not alt then
-      local ch = string_char(code)
-      -- work around native GTK-OSX's handling of Alt key
-      if ch:find('[%p%d]') and #keychain == 0 then
-        if buffer.anchor ~= buffer.current_pos then buffer:delete_back() end
-        buffer:add_text(ch)
-        events.emit('char_added', code)
-        return true
-      end
-    end
   else
-    if not KEYSYMS[code] then return end
     key = KEYSYMS[code]
+    if not key then return end
   end
   control = control and CTRL or ''
   shift = shift and SHIFT or ''
diff --git a/modules/textadept/menu.lua b/modules/textadept/menu.lua
index 196d685a..436f86bb 100644
--- a/modules/textadept/menu.lua
+++ b/modules/textadept/menu.lua
@@ -10,6 +10,20 @@ local gui = _G.gui
 -- This module, like _m.textadept.keys, should be 'require'ed last.
 module('_m.textadept.menu', package.seeall)
 
+-- Markdown:
+--
+-- ## Events
+--
+-- The following is a list of all menu events generated in
+-- `event_name(arguments)` format:
+--
+-- * **menu\_clicked** (menu\_id)<br />
+--   Called when a menu item is selected.
+--       - menu\_id: the numeric ID of the menu item set in
+--         [`gui.gtkmenu()`][gui_gtkmenu].
+--
+-- [gui_gtkmenu]: ../modules/gui.html#gtkmenu
+
 local SEPARATOR = 'separator'
 local b, v = 'buffer', 'view'
 local m_snippets = _m.textadept.snippets
@@ -121,24 +135,32 @@ menubar = {
     { L('Convert _Indentation'), { m_editing.convert_indentation } },
     { title = L('S_election'),
       { title = L('_Enclose in...'),
-        { L('_HTML Tags'), { m_editing.enclose, 'tag' } },
-        { L('HTML Single _Tag'), { m_editing.enclose, 'single_tag' } },
-        { L('_Double Quotes'), { m_editing.enclose, 'dbl_quotes' } },
-        { L('_Single Quotes'), { m_editing.enclose, 'sng_quotes' } },
-        { L('_Parentheses'), { m_editing.enclose, 'parens' } },
-        { L('_Brackets'), { m_editing.enclose, 'brackets' } },
-        { L('B_races'), { m_editing.enclose, 'braces' } },
-        { L('_Character Sequence'), { m_editing.enclose, 'chars' } },
+        { L('_HTML Tags'), {
+          function()
+            m_editing.enclose('<', '>')
+            local buffer = buffer
+            local pos = buffer.current_pos
+            while buffer.char_at[pos - 1] ~= 60 do pos = pos - 1 end -- '<'
+            buffer:insert_text(-1,
+                               '</'..buffer:text_range(pos, buffer.current_pos))
+          end
+        } },
+        { L('HTML Single _Tag'), { m_editing.enclose, '<', ' />' } },
+        { L('_Double Quotes'), { m_editing.enclose, '"', '"' } },
+        { L('_Single Quotes'), { m_editing.enclose, "'", "'" } },
+        { L('_Parentheses'), { m_editing.enclose, '(', ')' } },
+        { L('_Brackets'), { m_editing.enclose, '[', ']' } },
+        { L('B_races'), { m_editing.enclose, '{', '}' } },
       },
       { L('_Grow'), { m_editing.grow_selection, 1 } },
     },
     { title = L('Select i_n...'),
-      { L('_HTML Tag'), { m_editing.select_enclosed, 'tags' } },
-      { L('_Double Quote'), { m_editing.select_enclosed, 'dbl_quotes' } },
-      { L('_Single Quote'), { m_editing.select_enclosed, 'sng_quotes' } },
-      { L('_Parenthesis'), { m_editing.select_enclosed, 'parens' } },
-      { L('_Bracket'), { m_editing.select_enclosed, 'brackets' } },
-      { L('B_race'), { m_editing.select_enclosed, 'braces' } },
+      { L('_HTML Tag'), { m_editing.select_enclosed, '>', '<' } },
+      { L('_Double Quote'), { m_editing.select_enclosed, '"', '"' } },
+      { L('_Single Quote'), { m_editing.select_enclosed, "'", "'" } },
+      { L('_Parenthesis'), { m_editing.select_enclosed, '(', ')' } },
+      { L('_Bracket'), { m_editing.select_enclosed, '[', ']' } },
+      { L('B_race'), { m_editing.select_enclosed, '{', '}' } },
       { L('_Word'), { m_editing.current_word, 'select' } },
       { L('_Line'), { m_editing.select_line } },
       { L('Para_graph'), { m_editing.select_paragraph } },
diff --git a/modules/textadept/mime_types.lua b/modules/textadept/mime_types.lua
index f066e46b..e6023995 100644
--- a/modules/textadept/mime_types.lua
+++ b/modules/textadept/mime_types.lua
@@ -114,7 +114,6 @@ lexers = {}
 
 -- Generate lexer list
 local lexers_found = {}
-local lfs = require 'lfs'
 for lexer in lfs.dir(_HOME..'/lexers/') do
   if lexer:find('%.lua$') and lexer ~= 'lexer.lua' then
     lexers_found[lexer:match('^(.+)%.lua$')] = true
diff --git a/modules/textadept/run.lua b/modules/textadept/run.lua
index 3cae9e86..2203b129 100755..100644
--- a/modules/textadept/run.lua
+++ b/modules/textadept/run.lua
@@ -19,11 +19,9 @@ module('_m.textadept.run', package.seeall)
 --     * %(filename_noext) The name of the file excluding extension.
 function execute(command)
   local filepath = buffer.filename:iconv(_CHARSET, 'UTF-8')
-  local filedir, filename
+  local filedir, filename = '', filepath
   if filepath:find('[/\\]') then
     filedir, filename = filepath:match('^(.+[/\\])([^/\\]+)$')
-  else
-    filedir, filename = '', filepath
   end
   local filename_noext = filename:match('^(.+)%.')
   command = command:gsub('%%%b()', {
@@ -42,6 +40,15 @@ function execute(command)
   buffer:goto_pos(buffer.length)
 end
 
+-- Executes a compile or run command.
+-- @param cmd_table Either compile_command or run_command
+local function command(cmd_table)
+  if not buffer.filename then return end
+  buffer:save()
+  local action = cmd_table[buffer.filename:match('[^.]+$')]
+  if action then execute(type(action) == 'function' and action() or action) end
+end
+
 ---
 -- File extensions and their associated 'compile' actions.
 -- Each key is a file extension whose value is a either a command line string to
@@ -55,12 +62,7 @@ compile_command = {}
 -- Compiles the file as specified by its extension in the compile_command
 -- table.
 -- @see compile_command
-function compile()
-  if not buffer.filename then return end
-  buffer:save()
-  local action = compile_command[buffer.filename:match('[^.]+$')]
-  if action then execute(type(action) == 'function' and action() or action) end
-end
+function compile() command(compile_command) end
 
 ---
 -- File extensions and their associated 'go' actions.
@@ -75,12 +77,7 @@ run_command = {}
 -- Runs/executes the file as specified by its extension in the run_command
 -- table.
 -- @see run_command
-function run()
-  if not buffer.filename then return end
-  buffer:save()
-  local action = run_command[buffer.filename:match('[^.]+$')]
-  if action then execute(type(action) == 'function' and action() or action) end
-end
+function run() command(run_command) end
 
 ---
 -- A table of error string details.
@@ -112,7 +109,6 @@ function goto_error(pos, line_num)
     for _, error_detail in pairs(error_detail) do
       local captures = { line:match(error_detail.pattern) }
       if #captures > 0 then
-        local lfs = require 'lfs'
         local utf8_filename = captures[error_detail.filename]
         local filename = utf8_filename:iconv(_CHARSET, 'UTF-8')
         if lfs.attributes(filename) then
diff --git a/modules/textadept/session.lua b/modules/textadept/session.lua
index c8fc1d90..745638cc 100755..100644
--- a/modules/textadept/session.lua
+++ b/modules/textadept/session.lua
@@ -19,8 +19,6 @@ DEFAULT_SESSION = _USERHOME..'/session'
 SAVE_ON_QUIT = true
 -- end settings
 
-local lfs = require 'lfs'
-
 ---
 -- Loads a Textadept session file.
 -- Textadept restores split views, opened buffers, cursor information, and
@@ -33,16 +31,17 @@ function load(filename)
   local not_found = {}
   local f = io.open(filename or DEFAULT_SESSION, 'rb')
   if not f then
-    if not io.close_all() then return false end
+    io.close_all()
+    return false
   end
-  if not f then return false end
   local current_view, splits = 1, { [0] = {} }
+  local lfs_attributes = lfs.attributes
   for line in f:lines() do
     if line:find('^buffer:') then
       local anchor, current_pos, first_visible_line, filename =
         line:match('^buffer: (%d+) (%d+) (%d+) (.+)$')
       if not filename:find('^%[.+%]$') then
-        if lfs.attributes(filename) then
+        if lfs_attributes(filename) then
           io.open_file(filename)
         else
           not_found[#not_found + 1] = filename
@@ -77,8 +76,7 @@ function load(filename)
     elseif line:find('^current_view:') then
       local view_idx = line:match('^current_view: (%d+)')
       current_view = tonumber(view_idx) or 1
-    end
-    if line:find('^size:') then
+    elseif line:find('^size:') then
       local width, height = line:match('^size: (%d+) (%d+)$')
       if width and height then gui.size = { width, height } end
     end
diff --git a/modules/textadept/snapopen.lua b/modules/textadept/snapopen.lua
index f472b744..10690c75 100755..100644
--- a/modules/textadept/snapopen.lua
+++ b/modules/textadept/snapopen.lua
@@ -36,7 +36,7 @@ DEFAULT_DEPTH = 4
 MAX = 1000

 -- end settings

 

-local lfs = require 'lfs'

+local lfs_dir, lfs_attributes = lfs.dir, lfs.attributes

 local DEPTH = DEFAULT_DEPTH

 

 -- Determines whether or not the given file matches the given filter.

@@ -64,10 +64,10 @@ end
 -- @param filter The filter table.

 local function add_directory(dir, list, depth, filter)

   local string_match, string_gsub, MAX = string.match, string.gsub, MAX

-  for file in lfs.dir(dir) do

+  for file in lfs_dir(dir) do

     if not string_match(file, '^%.%.?$') then

       file = dir..(not WIN32 and '/' or '\\')..file

-      if lfs.attributes(file).mode == 'directory' then

+      if lfs_attributes(file).mode == 'directory' then

         if not exclude(file, filter.folders) and depth < DEPTH then

           add_directory(file, list, depth + 1, filter)

         end

diff --git a/modules/textadept/snippets.lua b/modules/textadept/snippets.lua
index 4d426532..95a80558 100755..100644
--- a/modules/textadept/snippets.lua
+++ b/modules/textadept/snippets.lua
@@ -34,6 +34,9 @@ module('_m.textadept.snippets', package.seeall)
 -- and `lua`. Style names are different lexer styles, most of which are in
 -- `lexers/lexer.lua`; examples are `whitespace`, `comment`, and `string`.
 --
+-- Snippet text should contain spaces instead of tabs since Textadept
+-- automatically converts spaces to tabs depending on the current settings.
+--
 -- ## Snippet Precedence
 --
 -- When searching for a snippet to expand in the `snippets` table, snippets in