Renamed modules/textadept/key_commands.lua to modules/textadept/keys.lua.

1 files changed, 652 insertions, 0 deletions

diff --git a/modules/textadept/keys.lua b/modules/textadept/keys.lua
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+-- Copyright 2007-2010 Mitchell mitchell<att>caladbolg.net. See LICENSE.
+
+local locale = _G.locale
+local events = _G.events
+
+---
+-- Manages and defines key commands in Textadept.
+-- This set of key commands is pretty standard among other text editors.
+module('_m.textadept.keys', package.seeall)
+
+-- Markdown:
+-- ## Overview
+--
+-- Key commands are defined in the global table `keys`. Each key-value pair in
+-- `keys` consists of either:
+--
+-- * A string representing a key command and an associated action table.
+-- * A string language name and its associated `keys`-like table.
+-- * A string style name and its associated `keys`-like table.
+-- * A string representing a key command and its associated `keys`-like table.
+--   (This is a keychain sequence.)
+--
+-- A key command string is built from a combination of the `CTRL`, `SHIFT`,
+-- `ALT`, and `ADD` constants as well as the pressed key itself. The value of
+-- `ADD` is inserted between each of `CTRL`, `SHIFT`, `ALT`, and the key.
+-- For example:
+--
+--     -- keys.lua:
+--     CTRL = 'Ctrl'
+--     SHIFT = 'Shift'
+--     ALT = 'Alt'
+--     ADD = '+'
+--     -- pressing control, shift, alt and 'a' yields: 'Ctrl+Shift+Alt+A'
+--
+-- For key values less than 255, Lua's [`string.char()`][string_char] is used to
+-- determine the key's string representation. Otherwise, the
+-- [`KEYSYMS`][keysyms] lookup table is used.
+--
+-- [string_char]: http://www.lua.org/manual/5.1/manual.html#pdf-string.char
+-- [keysyms]: ../modules/keys.html#KEYSYMS
+--
+-- An action table is a table consisting of either:
+--
+-- * A Lua function followed by a list of arguments to pass to that function.
+-- * A string representing a [buffer][buffer] or [view][view] function followed
+--   by its respective `'buffer'` or `'view'` string and then any arguments to
+--   pass to the resulting function.
+--
+--       `buffer.`_`function`_ by itself cannot be used because at the time of
+--       evaluation, `buffer.`_`function`_ would apply only to the current
+--       buffer, not for all buffers. By using this string reference system, the
+--       correct `buffer.`_`function`_ will be evaluated every time. The same
+--       applies to `view`.
+--
+-- [buffer]: ../modules/buffer.html
+-- [view]: ../modules/view.html
+--
+-- Language names are the names of the lexer files in `lexers/` such as `cpp`
+-- and `lua`. Style names are different lexer styles, most of which are in
+-- `lexers/lexer.lua`; examples are `whitespace`, `comment`, and `string`.
+--
+-- Key commands can be chained like in Emacs using keychain sequences. By
+-- default, the `Esc` key cancels the current keychain, but it can be redefined
+-- by setting the `keys.clear_sequence` field. Naturally, the clear sequence
+-- cannot be chained.
+--
+-- ## Settings
+--
+-- * `SCOPES_ENABLED`: Flag indicating whether scopes/styles can be used for key
+--   commands.
+-- * `CTRL`: The string representing the Control key.
+-- * `SHIFT`: The string representing the Shift key.
+-- * `ALT`: The string representing the Alt key (the Apple key on Mac OSX).
+-- * `ADD`: The string representing used to join together a sequence of Control,
+--   Shift, or Alt modifier keys.
+--
+-- ## Key Command Precedence
+--
+-- When searching for a key command to execute in the `keys` table, key commands
+-- in the current style have priority, followed by the  ones in the current lexer,
+-- and finally the ones in the global table.
+--
+-- ## Example
+--
+--     keys = {
+--       ['ctrl+f'] = { 'char_right', 'buffer' },
+--       ['ctrl+b'] = { 'char_left',  'buffer' },
+--       lua = {
+--         ['ctrl+c'] = { 'add_text', 'buffer', '-- ' },
+--         whitespace = {
+--           ['ctrl+f'] = { function() print('whitespace') 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, the global key command with the same shortcut is overriden and
+-- `whitespace` is printed to standard out.
+--
+-- ## Problems
+--
+-- All Lua functions must be defined BEFORE they are reference in key commands.
+-- Therefore, any module containing key commands should be loaded after all
+-- other modules, whose functions are being referenced, have been loaded.
+--
+-- ## Configuration
+--
+-- It is not recommended to edit Textadept's `core/ext/key_commands.lua`. You
+-- can either override or add to default key commands in your
+-- `~/.textadept/key_commands.lua` or `require` a separate module in your
+-- `~/.textadept/init.lua` instead of `ext/key_commands`.
+
+-- Windows and Linux key commands are listed in the first block.
+-- Mac OSX key commands are listed in the second block.
+
+-- settings
+local SCOPES_ENABLED = true
+local ADD = ''
+local CTRL = 'c'..ADD
+local SHIFT = 's'..ADD
+local ALT = 'a'..ADD
+-- end settings
+
+local keys = _M
+local b, v = 'buffer', 'view'
+local gui = gui
+
+-- CTRL = 'c'
+-- SHIFT = 's'
+-- ALT = 'a'
+-- ADD = ''
+-- Control, Shift, Alt, and 'a' = 'caA'
+-- Control, Shift, Alt, and '\t' = 'csa\t'
+
+if not MAC then
+  -- Windows and Linux key commands.
+
+  --[[
+    C:         D       H I J K   M               U
+    A:   A B C D E F G H   J K L M N   P   R S T U V W X Y Z
+    CS:  A B C D     G H I J K L M N O   Q     T U V   X Y Z
+    SA:  A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
+    CA:  A B C D E F G H   J K L M N O   Q R S T U V W X Y Z
+    CSA: A B C D E F G H   J K L M N O P Q R S T U V W X Y Z
+  ]]--
+
+  keys.clear_sequence = 'esc'
+
+  keys.ct = {} -- Textadept command chain
+
+  -- File
+  local m_session = _m.textadept.session
+  keys.cn  = { new_buffer   }
+  keys.co  = { io.open_file }
+  -- TODO: { 'reload', b }
+  keys.cs  = { 'save', b    }
+  keys.cS  = { 'save_as', b }
+  keys.cw  = { 'close', b   }
+  keys.cW  = { io.close_all }
+  -- TODO: { m_session.load } after prompting with open dialog
+  -- TODO: { m_session.save } after prompting with save dialog
+  keys.aq = { quit }
+
+  -- Edit
+  local m_editing = _m.textadept.editing
+  keys.cz = { 'undo', b       }
+  keys.cy = { 'redo', b       }
+  keys.cx = { 'cut', b        }
+  keys.cc = { 'copy', b       }
+  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['c\n\r'] = { m_editing.autocomplete_word, '%w_' } -- win32
+  keys.cq     = { m_editing.block_comment            }
+  -- TODO: { m_editing.current_word, 'delete' }
+  -- TODO: { m_editing.transpose_chars }
+  -- TODO: { m_editing.squeeze }
+  -- TODO: { m_editing.convert_indentation }
+  -- TODO: { m_editing.smart_cutcopy }
+  -- TODO: { m_editing.smart_cutcopy, 'copy' }
+  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'      },
+  }
+  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             },
+  }
+
+  -- Search
+  keys.cf = { gui.find.focus } -- find/replace
+  keys['f3'] = { gui.find.find_next }
+  -- Find Next is an when find pane is focused.
+  -- Find Prev is ap when find pane is focused.
+  -- Replace is ar when find pane is focused.
+  keys.cF = { gui.find.find_incremental }
+  -- Find in Files is ai when find pane is focused.
+  -- TODO: { gui.find.goto_file_in_list, true  }
+  -- TODO: { gui.find.goto_file_in_list, false }
+  keys.cg = { m_editing.goto_line }
+
+  -- Tools
+  keys['f2'] = { gui.command_entry.focus }
+  -- Run
+  local m_run = _m.textadept.run
+  keys.cr = { m_run.run     }
+  keys.cR = { m_run.compile }
+  -- Snippets
+  local m_snippets = _m.textadept.snippets
+  keys['\t']  = { m_snippets.insert         }
+  keys['s\t'] = { m_snippets.prev           }
+  keys.cai    = { m_snippets.cancel_current }
+  keys.caI    = { m_snippets.list           }
+  keys.ai     = { m_snippets.show_style     }
+
+  -- Buffers
+  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'          },
+    i      = { toggle_setting, 'indentation_guides' },
+    ['\t'] = { toggle_setting, 'use_tabs'           },
+    [' ']  = { toggle_setting, 'view_ws'            },
+  }
+  keys.cl    = { _m.textadept.mime_types.select_lexer }
+  keys['f5'] = { 'colourise', b, 0, -1     }
+
+  -- Views
+  keys.cav = {
+    n = { gui.goto_view, 1, false                    },
+    p = { gui.goto_view, -1, false                   },
+    S = { 'split', v                                 }, -- vertical
+    s = { 'split', v, false                          }, -- horizontal
+    w = { function() view:unsplit() return true end  },
+    W = { function() while view:unsplit() do end end },
+    -- TODO: { function() view.size = view.size + 10 end  }
+    -- TODO: { function() view.size = view.size - 10 end  }
+  }
+  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
+  }
+
+else
+  -- Mac OSX key commands
+
+  --[[
+    C:                     J     M               U   W X   Z
+    A:         D E     H   J K L                 U       Y
+    CS:      C D     G H I J K L M   O   Q   S T U V W X Y Z
+    SA:  A B C D       H I J K L M N O   Q R   T U V   X Y
+    CA:  A   C   E         J K L M N O   Q R S T U V W X Y Z
+    CSA: A   C D E     H   J K L M N O P Q R S T U V W X Y Z
+  ]]--
+
+  keys.clear_sequence = 'aesc'
+
+  keys.at = {} -- Textadept command chain
+
+  -- File
+  local m_session = _m.textadept.session
+  keys.an = { new_buffer   }
+  keys.ao = { io.open_file }
+  -- TODO: { 'reload', b }
+  keys.as = { 'save', b    }
+  keys.aS = { 'save_as', b }
+  keys.aw = { 'close', b   }
+  keys.aW = { io.close_all }
+  -- TODO: { m_session.load } after prompting with open dialog
+  -- TODO: { m_session.save } after prompting with save dialog
+  keys.aq = { quit }
+
+  -- Edit
+  local m_editing = _m.textadept.editing
+  keys.az  = { 'undo', b  }
+  keys.aZ  = { 'redo', b  }
+  keys.ax  = { 'cut', b   }
+  keys.ac  = { 'copy', b  }
+  keys.av  = { 'paste', b }
+  -- Delete is delete.
+  keys.aa  = { 'select_all', b }
+  keys.cm  = { m_editing.match_brace              }
+  keys.aE  = { m_editing.match_brace, 'select'    }
+  keys.esc = { m_editing.autocomplete_word, '%w_' }
+  keys.cq  = { m_editing.block_comment            }
+  -- TODO: { m_editing.current_word, 'delete' }
+  keys.ct = { m_editing.transpose_chars }
+  -- TODO: { m_editing.squeeze }
+  -- TODO: { m_editing.convert_indentation }
+  keys.ck = { m_editing.smart_cutcopy }
+  -- TODO: { m_editing.smart_cutcopy, 'copy' }
+  keys.cy = { 'paste', b }
+  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'      },
+  }
+  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             },
+  }
+
+  -- 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.ai = { gui.find.find_incremental }
+  keys.aF = {
+    function()
+      gui.find.in_files = true
+      gui.find.focus()
+    end
+  }
+  keys.cag = { gui.find.goto_file_in_list, true  }
+  keys.caG = { gui.find.goto_file_in_list, false }
+  keys.cg  = { m_editing.goto_line             }
+
+  -- Tools
+  keys['f2'] = { gui.command_entry.focus }
+  -- Run
+  local m_run = _m.textadept.run
+  keys.cr = { m_run.run     }
+  keys.cR = { m_run.compile }
+  -- Snippets
+  local m_snippets = _m.textadept.snippets
+  keys['\t']  = { m_snippets.insert         }
+  keys['s\t'] = { m_snippets.prev           }
+  keys.cai    = { m_snippets.cancel_current }
+  keys.caI    = { m_snippets.list           }
+  keys.ci     = { m_snippets.show_style     }
+
+  -- Buffers
+  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'          },
+    i      = { toggle_setting, 'indentation_guides' },
+    ['\t'] = { toggle_setting, 'use_tabs'           },
+    [' ']  = { toggle_setting, 'view_ws'            },
+  }
+  keys.cl    = { _m.textadept.mime_types.select_lexer }
+  keys['f5'] = { 'colourise', b, 0, -1     }
+
+  -- Views
+  keys.cv = {
+    n = { gui.goto_view, 1, false                    },
+    p = { gui.goto_view, -1, false                   },
+    S = { 'split', v                                 }, -- vertical
+    s = { 'split', v, false                          }, -- horizontal
+    w = { function() view:unsplit() return true end  },
+    W = { function() while view:unsplit() do end end },
+    -- TODO: { function() view.size = view.size + 10 end  }
+    -- TODO: { function() view.size = view.size - 10 end  }
+  }
+  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
+  }
+
+  -- Movement/selection commands
+  keys.cf  = { 'char_right',        b }
+  keys.cF  = { 'char_right_extend', b }
+  keys.caf = { 'word_right',        b }
+  keys.caF = { 'word_right_extend', b }
+  keys.cb  = { 'char_left',         b }
+  keys.cB  = { 'char_left_extend',  b }
+  keys.cab = { 'word_left',         b }
+  keys.caB = { 'word_left_extend',  b }
+  keys.cn  = { 'line_down',         b }
+  keys.cN  = { 'line_down_extend',  b }
+  keys.cp  = { 'line_up',           b }
+  keys.cP  = { 'line_up_extend',    b }
+  keys.ca  = { 'vc_home',           b }
+  keys.cA  = { 'home_extend',       b }
+  keys.ce  = { 'line_end',          b }
+  keys.cE  = { 'line_end_extend',   b }
+  keys.ch  = { 'delete_back',       b }
+  keys.cah = { 'del_word_left',     b }
+  keys.cd  = { 'clear',             b }
+  keys.cad = { 'del_word_right',    b }
+end
+
+user_dofile('key_commands.lua') -- load user key commands
+
+-- Do not edit below this line.
+
+-- optimize for speed
+local string = _G.string
+local string_char = string.char
+local string_format = string.format
+local pcall = _G.pcall
+local ipairs = _G.ipairs
+local next = _G.next
+local type = _G.type
+local unpack = _G.unpack
+local MAC = _G.MAC
+
+---
+-- Lookup table for key values higher than 255.
+-- If a key value given to 'keypress' is higher than 255, this table is used to
+-- return a string representation of the key if it exists.
+-- @class table
+-- @name KEYSYMS
+KEYSYMS = { -- from <gdk/gdkkeysyms.h>
+  [65056] = '\t', -- backtab; will be 'shift'ed
+  [65288] = '\b',
+  [65289] = '\t',
+  [65293] = '\n',
+  [65307] = 'esc',
+  [65535] = 'del',
+  [65360] = 'home',
+  [65361] = 'left',
+  [65362] = 'up',
+  [65363] = 'right',
+  [65364] = 'down',
+  [65365] = 'pup',
+  [65366] = 'pdown',
+  [65367] = 'end',
+  [65379] = 'ins',
+  [65470] = 'f1', [65471] = 'f2',  [65472] = 'f3',  [65473] = 'f4',
+  [65474] = 'f5', [65475] = 'f6',  [65476] = 'f7',  [65477] = 'f8',
+  [65478] = 'f9', [65479] = 'f10', [65480] = 'f11', [65481] = 'f12',
+}
+
+-- The current key sequence.
+local keychain = {}
+
+-- Clears the current key sequence.
+local function clear_key_sequence()
+  keychain = {}
+  gui.statusbar_text = ''
+end
+
+-- Helper function that gets commands associated with the current keychain from
+-- 'keys'.
+-- If the current item in the keychain is part of a chain, throw an error value
+-- of -1. This way, pcall will return false and -1, where the -1 can easily and
+-- efficiently be checked rather than using a string error message.
+local function try_get_cmd(active_table)
+  for _, key_seq in ipairs(keychain) do active_table = active_table[key_seq] end
+  if #active_table == 0 and next(active_table) then
+    gui.statusbar_text = locale.KEYCHAIN..table.concat(keychain, ' ')
+    error(-1, 0)
+  else
+    local func = active_table[1]
+    if type(func) == 'function' then
+      return func, { unpack(active_table, 2) }
+    elseif type(func) == 'string' then
+      local object = active_table[2]
+      if object == 'buffer' then
+        return buffer[func], { buffer, unpack(active_table, 3) }
+      elseif object == 'view' then
+        return view[func], { view, unpack(active_table, 3) }
+      end
+    else
+      error(locale.KEYS_UNKNOWN_COMMAND..tostring(func))
+    end
+  end
+end
+
+-- Tries to get a key command based on the lexer and current scope.
+local function try_get_cmd1(keys, lexer, scope)
+  return try_get_cmd(keys[lexer][scope])
+end
+
+-- Tries to get a key command based on the lexer.
+local function try_get_cmd2(keys, lexer)
+  return try_get_cmd(keys[lexer])
+end
+
+-- Tries to get a global key command.
+local function try_get_cmd3(keys)
+  return try_get_cmd(keys)
+end
+
+-- Handles Textadept keypresses.
+-- It is called every time a key is pressed, and based on lexer and scope,
+-- executes a command. The command is looked up in the global 'keys' key
+-- command table.
+-- @return whatever the executed command returns, true by default. A true
+--   return value will tell Textadept not to handle the key afterwords.
+local function keypress(code, shift, control, alt)
+  local buffer = buffer
+  local key
+  --print(code, string.char(code))
+  if code < 256 then
+    key = string_char(code)
+    shift = false -- for printable characters, key is upper case
+    if MAC 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]
+  end
+  control = control and CTRL or ''
+  shift = shift and SHIFT or ''
+  alt = alt and ALT or ''
+  local key_seq = string_format('%s%s%s%s', control, shift, alt, key)
+
+  if #keychain > 0 and key_seq == keys.clear_sequence then
+    clear_key_sequence()
+    return true
+  end
+
+  local lexer = buffer:get_lexer_language()
+  keychain[#keychain + 1] = key_seq
+  local ret, func, args
+  if SCOPES_ENABLED then
+    local style = buffer.style_at[buffer.current_pos]
+    local scope = buffer:get_style_name(style)
+    --print(key_seq, 'Lexer: '..lexer, 'Scope: '..scope)
+    ret, func, args = pcall(try_get_cmd1, keys, lexer, scope)
+  end
+  if not ret and func ~= -1 then
+    ret, func, args = pcall(try_get_cmd2, keys, lexer)
+  end
+  if not ret and func ~= -1 then
+    ret, func, args = pcall(try_get_cmd3, keys)
+  end
+
+  if ret then
+    clear_key_sequence()
+    if type(func) == 'function' then
+      local ret, retval = pcall(func, unpack(args))
+      if ret then
+        if type(retval) == 'boolean' then return retval end
+      else
+        error(retval)
+      end
+    end
+    return true
+  else
+    -- Clear key sequence because it's not part of a chain.
+    -- (try_get_cmd throws error number -1.)
+    if func ~= -1 then
+      local size = #keychain - 1
+      clear_key_sequence()
+      if size > 0 then -- previously in a chain
+        gui.statusbar_text = locale.KEYS_INVALID
+        return true
+      end
+    else
+      return true
+    end
+  end
+end
+events.connect('keypress', keypress, 1)