Appendix - Textadept

# Textadept

- Home |
- Download |
- Lua API |
- Source |
- Language Modules |
- Stats |
- Wiki |
- Mailing List

# Appendix

## Lua Patterns

The following is taken from the Lua 5.2 Reference Manual.

Character Class:

A character class is used to represent a set of characters. The following combinations are allowed in describing a character class:

- `x`: (where x is not one of the magic characters `^$()%.[]*+-?`) represents the character x itself.
- `.`: (a dot) represents all characters.
- `%a`: represents all letters.
- `%c`: represents all control characters.
- `%d`: represents all digits.
- `%g`: represents all printable characters except space.
- `%l`: represents all lowercase letters.
- `%p`: represents all punctuation characters.
- `%s`: represents all space characters.
- `%u`: represents all uppercase letters.
- `%w`: represents all alphanumeric characters.
- `%x`: represents all hexadecimal digits.
- `%``x`: (where x is any non-alphanumeric character) represents the character x. This is the standard way to escape the magic characters. Any punctuation character (even the non magic) can be preceded by a ‘`%`’ when used to represent itself in a pattern.
- `[set]`: represents the class which is the union of all characters in set. A range of characters can be specified by separating the end characters of the range with a ‘`-`’. All classes `%`x described above can also be used as components in set. All other characters in set represent themselves. For example, `[%w_]` (or `[_%w]`) represents all alphanumeric characters plus the underscore, `[0-7]` represents the octal digits, and `[0-7%l%-]` represents the octal digits plus the lowercase letters plus the ‘`-`’ character.
  The interaction between ranges and classes is not defined. Therefore, patterns like `[%a-z]` or `[a-%%]` have no meaning.
- `[^set]`: represents the complement of set, where set is interpreted as above.

For all classes represented by single letters (`%a`, `%c`, etc.), the corresponding uppercase letter represents the complement of the class. For instance, `%S` represents all non-space characters.

The definitions of letter, space, and other character groups depend on the current locale. In particular, the class `[a-z]` may not be equivalent to `%l`.

Pattern Item:

A pattern item can be

- a single character class, which matches any single character in the class;
- a single character class followed by ‘`*`’, which matches 0 or more repetitions of characters in the class. These repetition items will always match the longest possible sequence;
- a single character class followed by ‘`+`’, which matches 1 or more repetitions of characters in the class. These repetition items will always match the longest possible sequence;
- a single character class followed by ‘`-`’, which also matches 0 or more repetitions of characters in the class. Unlike ‘`*`’, these repetition items will always match the shortest possible sequence;
- a single character class followed by ‘`?`’, which matches 0 or 1 occurrence of a character in the class;
- `%n`, for n between 1 and 9; such item matches a substring equal to the n-th captured string (see below);
- `%bxy`, where x and y are two distinct characters; such item matches strings that start with x, end with y, and where the x and y are balanced. This means that, if one reads the string from left to right, counting +1 for an x and -1 for a y, the ending y is the first y where the count reaches 0. For instance, the item `%b()` matches expressions with balanced parentheses.
- `%f[set]`, a frontier pattern; such item matches an empty string at any position such that the next character belongs to set and the previous character does not belong to set. The set set is interpreted as previously described. The beginning and the end of the subject are handled as if they were the character `'\0'`.

Pattern:

A pattern is a sequence of pattern items. A ‘`^`’ at the beginning of a pattern anchors the match at the beginning of the subject string. A ‘`$`’ at the end of a pattern anchors the match at the end of the subject string. At other positions, ‘`^`’ and ‘`$`’ have no special meaning and represent themselves.

Captures:

A pattern can contain sub-patterns enclosed in parentheses; they describe captures. When a match succeeds, the substrings of the subject string that match captures are stored (captured) for future use. Captures are numbered according to their left parentheses. For instance, in the pattern `"(a*(.)%w(%s*))"`, the part of the string matching `"a*(.)%w(%s*)"` is stored as the first capture (and therefore has number 1); the character matching “`.`” is captured with number 2, and the part matching “`%s*`” has number 3.

As a special case, the empty capture `()` captures the current string position (a number). For instance, if we apply the pattern `"()aa()"` on the string `"flaaap"`, there will be two captures: 3 and 5.

## Curses Compatibility

Textadept 5.5 beta introduced a curses version that can run in a terminal emulator. However, since curses is quite low-level in terms of graphics capability compared to GTK+, the curses version of Textadept lacks some features in its editing component Scintilla and in general:

- Any settings with alpha values are not supported.
- Autocompletion lists cannot show images (pixmap surfaces are not supported). Instead, they show the first character in the string passed to `buffer:register_image()`.
- Buffered and two-phase drawing is not supported.
- Call tip arrows are not displayed (`surface->Polygon()` is not supported for drawing arrow shapes).
- Caret settings like period, line style, and width are not supported (terminals use block carets with their own period definitions).
- Code pages other than UTF-8 have not been tested and it is possible some curses implementations do not support them.
- Edge lines are not displayed properly (the line is drawn over by text lines).
- Extra ascent and decent for lines is not supported.
- Fold lines are not supported (`surface->LineTo()` is not supported).
- Indentation guides are not visible (pixmap surfaces are not supported).
- Indicators other than `INDIC_ROUNDBOX` and `INDIC_STRAIGHTBOX` are not drawn (`surface->LineTo()` is not supported for drawing indicator shapes and pixmap surfaces are not supported). Translucent drawing and rounded corners are not supported either.
- Insert mode caret is not drawn properly (no way to detect it from within `surface->FillRectangle()`).
- Margins are overwritten by long lines when scrolling to the right.
- Marker types other than `SC_MARK_CHARACTER` are not drawn (pixmap surfaces are not supported and `surface->LineTo()` is not supported for drawing marker shapes).
- Mouse interactions, cursor types, and hotspots are not supported.
- Up to 16 colors are supported: black (`0x000000`), red (`0x800000`), green (`0x008000`), yellow (`0x808000`), blue (`0x000080`), magenta (`0x800080`), cyan (`0x008080`), white (`0xC0C0C0`), light black (`0x404040`), light red (`0xFF0000`), light green (`0x00FF00`), light yellow (`0xFFFF00`), light blue (`0x0000FF`), light magenta (`0xFF00FF`), light cyan (`0x00FFFF`), and light white (`0xFFFFFF`). Even if your terminal uses a different color map, you must use these color values with Scintilla; unrecognized colors are set to white by default. For some terminals, you may need to set a lexer style’s `bold` attribute in order to use the light color variant.
- Scroll bars are not supported.
- Some key sequences are not recognized by the terminal or have unexpected key
- codes.
- Some styles settings like font name, font size, and italic do not display properly (terminals use one only font, size and variant).
- Viewing whitespace does not show the “Tab” character arrows (`surface->LineTo()` is not supported for drawing arrows).
- Visual wrap flags are not supported (`surface->LineTo()` is not supported).
- X selections (primary and secondary) are not integrated into the clipboard.
- Zoom is not supported (terminal font size is fixed).

## Migration Guides

### Textadept 5 to 6

Textadept 6 introduces some API changes.

#### Function Changes

##### `buffer`

Some of the “get” and “set” functions in `buffer` have been converted to properties:

- `buffer:annotation_get_text(line)` -> `buffer.annotation_text[line]`
- `buffer:annotation_set_text(line, text)` -> `buffer.annotation_text[line] = text`
- `buffer:auto_c_get_current()` -> `buffer.auto_c_current`
- `buffer:auto_c_get_current_text()` -> `buffer.auto_c_current_text`
- `buffer:get_lexer_language()` -> `buffer.lexer_language`
- `buffer:get_property(key)` -> `buffer.property[key]`
- `buffer:get_property_expanded(key)` -> `buffer.property_expanded[key]`
- `buffer:get_tag(tag_num)` -> `buffer.tag[tag_num]`
- `buffer:margin_get_text(line)` -> `buffer.margin_text[line]`
- `buffer:margin_set_text(line, text)` -> `buffer.margin_text[line] = text`
- `buffer:marker_set_alpha(marker_num, alpha)` -> `buffer.marker_alpha[marker_num] = alpha`
- `buffer:marker_set_back(marker_num, color)` -> `buffer.marker_back[marker_num] = color`
- `buffer:marker_set_back_selected(marker_num, color)` -> `buffer.marker_back_selected[marker_num] = color`
- `buffer:marker_set_fore(marker_num, color)` -> `buffer.marker_fore[marker_num] = color`
- `buffer:set_fold_flags(flags)` -> `buffer.fold_flags = flags`
- `buffer:set_lexer_language(language_name)` -> `buffer.lexer_language = language_name`
- `buffer:style_get_font(style_num)` -> `buffer.style_font[style_num]`

These changes will affect custom themes.

##### `goto_required`

`_M.lua.goto_required()`, `_M.php.goto_required()`, and `_M.ruby.goto_required()` have all been removed. They are inaccurate when projects re-define or define their own search paths.

##### `prepare_for_save`

`_M.textadept.editing.prepare_for_save()` was moved directly into an event handler and cannot be called separately anymore.

##### Sessions

`_M.textadept.session.prompt_load()` and `_M.textadept.session.prompt_save()` functionality has been moved into `_M.textadept.session.load()` and `_M.textadept.session.save()`. Therefore, replace all instances of `prompt_load` and `prompt_save` with `load` and `save` respectively.

##### Adeptsense

`_M.textadept.adeptsense.complete_symbol()` and `_M.textadept.adeptsense.show_documentation()` functionality has been moved into `_M.textadept.adeptsense.complete()` and `_M.textadept.adeptsense.show_apidoc()`. Therefore, replace all instances of `complete_symbol` and `show_documentation` with `complete` and `show_apidoc`.

##### `user_dofile`

`_G.user_dofile()` was removed. Use `dofile(_USERHOME..'/file.lua')` instead.

##### `gtkmenu`

`gui.gtkmenu()` was renamed to `gui.menu()`. Therefore, replace all instances of `gui.gtkmenu` with `gui.menu`.

##### Bookmarks

`_M.textadept.bookmarks.add()` and `_M.textadept.bookmarks.remove()` were consolidated into `_M.textadept.bookmarks.toggle()`. Replace `add()` with `toggle(true)` and `remove()` with `toggle(false)`. `toggle()` functionality otherwise remains the same.

##### `rebuild_command_tables`

`_M.textadept.menu.rebuild_command_tables()` was integrated into `_M.textadept.menu.set_menubar()`. Therefore, remove all calls to `rebuild_command_tables()` after `set_menubar()`.

##### `execute`

`_M.textadept.run.execute()` was removed. Use `_M.textadept.run.run()` and `_M.textadept.run.compile()` exclusively.

### Textadept 4 to 5

Lua has been upgraded from 5.1 to 5.2, so many scripts written for Textadept 4 are not compatible with Textadept 5. Since incompatible scripts may cause crashes on startup, the following guide will help you migrate your scripts from Textadept 4 to Textadept 5. While this guide is not exhaustive, it covers the changes I had to make to Textadept’s internals.

#### Module Changes

##### Syntax Changes

Although Lua 5.2 only deprecates Lua 5.1’s `module` syntax, Textadept 5 removes it. Therefore, replace

    -- File ~/.textadept/modules/foo.lua
    module('_m.foo', package.seeall)

    function bar()
      ...
    end

    ...

and

    -- File ~/.textadept/init.lua
    require 'textadept'
    require 'foo'

with

    -- File ~/.textadept/modules/foo.lua
    local M = {}

    function M.bar()
      ...
    end

    ...

    return M

or

    local M = {}
    local _ENV = M
    if setfenv then setfenv(1, _ENV) end -- LuaJIT support

    function bar()
      ...
    end

    function baz()
      bar()
    end

    return M

and

    -- File ~/.textadept/init.lua
    _M.textadept = require 'textadept'
    _M.foo = require 'foo'

Notice that `_M` is the new module table instead of `_m`. More on this later.

##### Module References

Replace all instances of `_M` (a reference created by `module()` that holds the current module table) with `M` (the local module table you created).

Also, prefix all instances of internal module function calls with `M` if you are not using `_ENV`. For example, change

    module('foo', package.seeall)

    function bar()
      ...
    end

    function baz()
      bar()
    end

to

    local M = {}

    function M.bar()
      ...
    end

    function M.baz()
      M.bar()
    end

    return M

##### LuaDoc

If you use LuaDoc for your modules, you can still document them like this:

    local M = {}

    --[[ This comment is for LuaDoc
    ---
    -- This is the documentation for module foo.
    module('foo')]]

    ---
    -- Documentation for bar.
    -- ...
    -- @name bar
    function M.bar()
      ...
    end

    return M

##### Global Module Table

Originally, I wanted to use `_M` as the global table that contains modules, but Lua 5.1’s modules used `_M` silently, so I had to settle with `_m`. Now that modules have been removed, `_M` is available again and is used. Therefore, replace all instances of `_m` with `_M`. In Textadept, you can easily do a search and replace with “Match Case” and “Whole Words” checked – this is what I did when upgrading Textadept’s internals.

#### Function Changes

##### `unpack`

`unpack()` has been renamed to `table.unpack()`. Replace all instances of `unpack` with `table.unpack`.

##### `xpcall`

`xpcall()` accepts error function parameters so you can change code from

    local args = {...}
    xpcall(function() return f(unpack(args)) end, error_function)

to

    xpcall(f, error_function, ...)

However, this is not required.

##### `loadstring`

`loadstring()` has been replaced by `load()` since the latter now recognizes a string chunk. Replace all instances of `loadstring` with `load`.

##### `setfenv`

`setfenv()` has been removed. In some cases, use `load()` with an environment instead. For example, change

    local f, err = loadstring(command)
    if err then error(err) end
    setfenv(f, env)()

to

    local f, err = load(command, nil, 'bt', env)
    if err then error(err) end
    f()

(The `'bt'` is necessary for loading both binary and text chunks.)

If instead you want to set a function’s environment, change

    setfenv(f, env)

to

    debug.setupvalue(f, 1, env)

##### `getfenv`

`getfenv()` has been removed. Change

    local env = getfenv(f)

to

    local debug = require 'debug'
    local env = debug.getupvalue(f, 1)

##### `os.execute`

`os.execute()`’s function parameters have changed. If you are only interested in the return code, change

    local code = os.execute(cmd)

to

    local _, _, code = os.execute(cmd)

##### `localize`

Localization is done using a global table `_L` instead of calling `locale.localize()`. Replace all instances of `locale.localize('message')` with `_L['message']`. This allows messages to be modified via scripts if desirable.

##### `current_word`

`_M.textadept.editing.current_word()` has been renamed to `select_word()` and does not take any parameters. There is a `_M.textadept.keys.utils.delete_word()` function that replaces `current_word('delete')`. You can use it or create a new function:

    local function delete_word()
      _M.textadept.editing.select_word()
      buffer:delete_back()
    end

#### Theme Changes

Any custom themes need to be changed to remove the `module` syntax. Usually this involves changing

    module('lexer', package.seeall)

    colors = {
      ...
    }

    style_nothing = style { ... }
    style_class = style { fore = colors.light_yellow }
    ...
    style_identifier = style_nothing

    ...

    style_default = style {
      ...
    }
    style_line_number = { fore = colors.dark_grey, back = colors.black }
    ...

to

    local l, color, style = lexer, lexer.color, lexer.style

    l.colors = {
      ...
    }

    l.style_nothing = style { ... }
    l.style_class = style { fore = l.colors.light_yellow }
    ...
    l.style_identifier = l.style_nothing

    ...

    l.style_default = style {
      ...
    }
    l.style_line_number = { fore = l.colors.dark_grey, back = l.colors.black }
    ...

Notice the `l.` prefix before most identifiers.

### Textadept 3 to 4

#### Key and Menu Changes

Textadept 4 allow key bindings to appear in menus, but only simple ones, not keychains. Therefore, Textadept’s key bindings have changed radically, as has the menu structure and menu mnemonics. In order for key bindings to appear in menus, `_m.textadept.menu` needs to know which commands are assigned to which keys. Therefore, the menu module needs to be `require`d after `_m.textadept.keys`. If your ~/.textadept/init.lua is calling `require 'textadept'`, you do not have to make any changes. If you are loading individual modules from `_m.textadept`, ensure `_m.textadept.menu` is loaded after `_m.textadept.keys`.

On Mac OSX, key binding definition has changed. `m` is now ⌘ (command) and `a` is now ⌥ (alt/option). `c` remains ^ (control). Previously `a` was ⌘ and ⌥ was undefined. Please note, however, that not all ⌥ combinations by themselves will work since that key is typically used to compose locale-dependent characters.

#### Function Changes

##### `select_scope`

`_m.textadept.editing.select_scope()` was renamed to `select_style()`. Therefore, replace all instances of `_m.textadept.editing.select_scope` with `_m.textadept.editing.select_style`.

##### `SAVE_STRIPS_WS`

`_m.textadept.editing.SAVE_STRIPS_WS` was renamed to `STRIP_WHITESPACE_ON_SAVE`. Replace all instances of `_m.textadept.editing.SAVE_STRIPS_WS` with `_m.textadept.editing.STRIP_WHITESPACE_ON_SAVE`.

### Textadept 2 to 3

#### Module Changes

##### Core Extensions

There are no more core extention modules (previously in core/ext/). They have been relocated to modules/textadept/ so putting

    require 'textadept'

in your ~/.textadept/init.lua will load all the modules you would expect. Please see the preferences page for instructions on how to load specific modules.

##### Autoloading

Key bindings in ~/.textadept/key_commands.lua and snippets in ~/.textadept/snippets.lua are no longer auto-loaded. Instead, modify `keys` and/or `snippets` from within your ~/.textadept/init.lua or a file loaded by ~/.textadept/init.lua.

#### Function Changes

Textadept has a brand new Lua API. It is likely that any external scripts, including themes, need to be rewritten.

Here is a summary of API changes:

- `_m.textadept.lsnippets` renamed to `_m.textadept.snippets`.
- `textadept.events` renamed to `_G.events`.
  - `events.handle()` renamed to `events.emit()`.
  - `events.add_handler()` renamed to `events.connect()`.
- `textadept.constants` renamed to `_SCINTILLA.constants`.
- `textadept.buffer_functions` renamed to `_SCINTILLA.functions`.
- `textadept.buffer_properties` renamed to `_SCINTILLA.properties`.
- `textadept.buffers` renamed to `_BUFFERS`.
- `textadept.views` renamed to `_VIEWS`.
- New `gui` module.
  - Renamed `textadept._print()` to `gui._print()`.
  - Renamed `textadept.check_focused_buffer()` to `gui.check_focused_buffer()`.
  - Renamed `textadept.clipboard_text` to `gui.clipboard_text`.
  - Renamed `textadept.context_menu` to `gui.context_menu`.
  - Renamed `textadept.command_entry` to `gui.command_entry`.
  - Renamed `textadept.dialog` to `gui.dialog()`.
  - Renamed `textadept.docstatusbar_text` to `gui.docstatusbar_text`.
  - Renamed `textadept.find` to `gui.find`.
  - Renamed `textadept.focused_doc_pointer` to `gui.focused_doc_pointer`.
  - Renamed `textadept.get_split_table()` to `gui.get_split_table()`.
  - Renamed `textadept.gtkmenu()` to `gui.gtkmenu()`.
  - Renamed `textadept.goto_view()` to `gui.goto_view()`.
  - Renamed `textadept.menubar` to `gui.menubar`.
  - Renamed `textadept.print()` to `gui.print()`.
  - Renamed `textadept.size` to `gui.size`.
  - Renamed `textadept.statusbar_text` to `gui.statusbar_text`.
  - Renamed `textadept.switch_buffer()` to `gui.switch_buffer()`.
  - Renamed `textadept.title` to `gui.title`.
  - Renamed `textadept.new_buffer()` to `new_buffer()`.
  - Renamed `textadept.quit()` to `quit()`.
  - Renamed `textadept.reset()` to `reset()`.
  - Renamed `textadept.user_dofile()` to `user_dofile()`.
  - Renamed `textadept.iconv()` to `string.iconv()`.
  - Renamed `textadept.session_file` to `_SESSIONFILE`.
- Removed global `textadept` module.