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diff --git a/.config/emacs/lisp/evil/doc/source/faq.rst b/.config/emacs/lisp/evil/doc/source/faq.rst deleted file mode 100644 index d389df0..0000000 --- a/.config/emacs/lisp/evil/doc/source/faq.rst +++ /dev/null @@ -1,118 +0,0 @@ -Frequently Asked Questions -========================== - -Problems with the escape key in the terminal --------------------------------------------- - -A common problem when using Evil in terminal mode is a certain delay -after pressing the escape key. Even more, when pressing the escape key -followed quickly by another key the command is recognized as -:kbd:`M-<key>` instead of two separate keys: :kbd:`ESC` followed by -:kbd:`<key>`. In fact, it is perfectly valid to simulate -:kbd:`M-<key>` by pressing :kbd:`ESC <key>` quickly (but see below). - -The reason for this is that in terminal mode a key sequence involving -the meta key (or alt key) always generates a so called "escape -sequence", i.e. a sequence of two events sent to Emacs, the first -being :kbd:`ESC` and the second the key pressed simultaneously. The -problem is that pressing the escape key itself also generates the -:kbd:`ESC` event. Thus, if Emacs (and therefore Evil) receives an -:kbd:`ESC` event there is no way to tell whether the escape key has -been pressed (and no further event will arrive) or a :kbd:`M-<key>` -combination has been pressed (and the :kbd:`<key>` event will arrive -soon). In order to distinguish both situations Evil does the -following. After receiving an :kbd:`ESC` event Evil waits for a short -time period (specified by the variable :elisp:ref:`evil-esc-delay` -which defaults to 0.01 seconds) for another event. If no other event -arrives Evil assumes that the plain escape key has been pressed, -otherwise it assumes a :kbd:`M-<key>` combination has been pressed and -combines the :kbd:`ESC` event with the second one. Because a -:kbd:`M-<key>` sequence usually generates both events in very quick -succession, 0.01 seconds are usually enough and the delay is hardly -noticeable by the user. - -If you use a terminal multiplexer like *tmux* or *screen* the -situation may be worse. These multiplexers have exactly the same -problem recognizing :kbd:`M-<key>` sequences and often introduce their -own delay for the :kbd:`ESC` key. There is no way for Evil to -influence this delay. In order to reduce it you must reconfigure your -terminal multiplexer. - -Note that this problem should not arise when using Evil in graphical -mode. The reason is that in this case the escape key itself generates -a different command, namely ``escape`` (a symbol) and hence Evil can -distinguish whether the escape key or a :kbd:`M-<key>` combination has -been pressed. But this also implies that pressing :kbd:`ESC` followed -by <key> cannot be used to simulate :kbd:`M-<key>` in graphical mode! - - -Underscore is not a word character ----------------------------------- - -An underscore ``_`` is a word character in Vim. This means that word -motions like :kbd:`w` skip over underlines in a sequence of letters as -if it was a letter itself. In contrast, in Evil the underscore is -often a non-word character like operators, e.g. ``+``. - -The reason is that Evil uses Emacs' definition of a word and this -definition does often not include the underscore. In Emacs word -characters are determined by the syntax-class of the buffer. The -syntax-class usually depends on the major-mode of this buffer. This -has the advantage that the definition of a "word" may be adapted to -the particular type of document being edited. Evil uses Emacs' -definition and does not simply use Vim's definition in order to be -consistent with other Emacs functions. For example, word characters -are exactly those characters that are matched by the regular -expression character class ``[:word:]``. - -If you would be satisfied by having the :kbd:`*` and :kbd:`#` searches -use symbols instead of words, this can be achieved by setting the -:elisp:ref:`evil-symbol-word-search` variable to ``t``. - -If you want the underscore to be recognised as word character for other -motions, you can modify its entry in the syntax-table: - -.. code-block:: elisp - - (modify-syntax-entry ?_ "w") - -This gives the underscore the 'word' syntax class. You can use a -mode-hook to modify the syntax-table in all buffers of some mode, -e.g.: - -.. code-block:: elisp - - (add-hook 'c-mode-common-hook - (lambda () (modify-syntax-entry ?_ "w"))) - -This gives the underscore the word syntax-class in all C-like buffers. - -Similarly to Emacs' definition of a word, the definition of a "symbol" is also -dependent on the syntax-class of the buffer, which often includes the -underscore. The default text objects keymap associates kbd::`o` with the symbol -object, making kbd::`cio` a good alternative to Vim's kbd::`ciw`, for example. -The following will swap between the word and symbol objects in the keymap: - -.. code-block:: elisp - - (define-key evil-outer-text-objects-map "w" 'evil-a-symbol) - (define-key evil-inner-text-objects-map "w" 'evil-inner-symbol) - (define-key evil-outer-text-objects-map "o" 'evil-a-word) - (define-key evil-inner-text-objects-map "o" 'evil-inner-word) - -This will not change the motion keys, however. One way to make word motions -operate as symbol motions is to alias the ``evil-word`` *thing* [#thingatpt]_ to -the ``evil-symbol`` thing: - -.. code-block:: elisp - - (defalias 'forward-evil-word 'forward-evil-symbol) - - -.. rubric:: Footnotes - -.. [#thingatpt] Many of Evil's text objects and motions are defined in - terms of the *thingatpt* library, which in this case are defined - entirely in terms of ``forward-THING`` functions. Thus aliasing - one to another should make all motions and text objects implemented - in terms of that *thing* behave the same. |