diff options
Diffstat (limited to 'Emacs/.config/emacs/config.org')
| -rw-r--r-- | Emacs/.config/emacs/config.org | 117 |
1 files changed, 84 insertions, 33 deletions
diff --git a/Emacs/.config/emacs/config.org b/Emacs/.config/emacs/config.org index 2d91a41..b26f9c5 100644 --- a/Emacs/.config/emacs/config.org +++ b/Emacs/.config/emacs/config.org @@ -1654,36 +1654,55 @@ xwidget." (xwidget-webkit-browse-url (concat "https://" engine "/?q=" query))))) #+end_src ** Eshell -Eshell is the integrated shell environment for Emacs. Though it isn't -necessarily *the best* shell, it really suits the 'integrated -computing environment' moniker that Emacs gets. - -It may be argued that Emacs integrates within itself many of the -functionalities that one would use within a shell or terminal. Stuff -like compilation, file management, large scale text manipulation could -be done through Emacs' own tools (~compile~, ~dired~ and ~occur~ come -to mind). However, I'd argue that eshell's greatest ability comes from -it's separation (or perhaps better phrased, *integration*) of two -'parsers': the Lisp parser and the Shell parser. With these parsers -you can mix and match at will for use in the shell, which grants -greater power than many shells I know of. - -Setup a function that /toggles/ the eshell window rather than just -opening it via ~+dx/toggle-buffer~. Along with that setup the prompt -so it looks a bit nicer and add pretty symbols to eshell. +*** Why Eshell? +Eshell is the integrated shell environment for Emacs. I argue that it +is the best shell/command interpreter to use in Emacs. + +Eshell is unlike the alternatives in Emacs as it's a /shell/ first, +not a terminal emulator. It has the ability to spoof some aspects of a +terminal emulator (through the shell parser), but it is NOT a terminal +emulator. + +I'd say the killer benefits of eshell (which would appeal to Emacs +users) are due to eshell being written in Emacs lisp: +- incredible integration with Emacs utilities (such as ~dired~, + ~find-file~, any read functions, to name a few) +- very extensible, easy to write new commands which leverage Emacs + commands as well as external utilities +- agnostic of platform: "eshell/cd" will call the underlying change + directory function for you, so commands will (usually) mean the same + thing regardless of platform + - this means as long as Emacs runs, you can run eshell + +However, my favourite feature of eshell is the set of evaluators that +run on command input. Some of the benefits listed above come as a +result of this powerful feature. These evaluators are describe below. + +Lisp evaluator: works on braced expressions, evaluating them as Lisp +expressions. Any returned objects are printed. This makes eshell an +Emacs Lisp REPL! + +External evaluator: works within curly braces, evaluating them via +some external shell process (like sh). This makes eshell a (dumb) +terminal emulator! + +The alias evaluator is the top level evaluator. It is the main +evaluator for each expression given to eshell. When given an +expression it tries to evaluate it by testing against these conditions +(going to the next if it doesn't find it): +- it's an alias defined by the user or in the ~eshell/~ namespace of + functions (simplest evaluator) +- it's some form of lisp expression (lisp evaluator) +- it's an external command (bash evaluator) + +Essentially, you get the best of both Emacs and external shell +programs *ALL WITHIN* Emacs for free. +*** Eshell bindings +Bind some evil-like movements for easy shell usage, and a toggle +function to pull up the eshell quickly. #+begin_src emacs-lisp (use-package eshell - :commands +shell/toggle-shell - :display - ("\\*e?shell\\*" ; for general shells as well - (display-buffer-at-bottom) - (window-height . 0.25)) - :pretty - (eshell-mode-hook - ("lambda" . "λ") - ("numberp" . "ℤ") - ("t" . "⊨") - ("nil" . "Ø")) + :commands +shell/toggle-eshell :general (leader "tt" #'+shell/toggle-eshell) @@ -1704,6 +1723,40 @@ so it looks a bit nicer and add pretty symbols to eshell. (recenter)) "k" #'eshell-kill-process)))) :config + (+oreo/create-toggle-function + +shell/toggle-eshell + "*eshell*" + eshell)) +#+end_src +*** Eshell pretty symbols and display +Pretty symbols and a display record. +#+begin_src emacs-lisp +(use-package eshell + :pretty + (eshell-mode-hook + ("lambda" . "λ") + ("numberp" . "ℤ") + ("t" . "⊨") + ("nil" . "Ø")) + :display + ("\\*e?shell\\*" ; for general shells as well + (display-buffer-at-bottom) + (window-height . 0.25))) +#+end_src +*** Eshell variables and aliases +Set some sane defaults, a banner and a prompt. The prompt checks for +a git repo in the current directory and provides some extra +information in that case (in particular, branch name and if there any +changes that haven't been committed). + +Also ~eshell/goto~, which is actually a command accessible from within +eshell (this is because ~eshell/*~ creates an accessible function +within eshell with name ~*~). ~eshell/goto~ makes it easier to change +directories by using Emacs to provide an interface (which is a faster +loop than ~cd ..; ls -l~). +#+begin_src emacs-lisp +(use-package eshell + :config (defun +eshell/get-git-properties () (let* ((git-branch (shell-command-to-string "git branch")) (is-repo (string= (substring git-branch 0 1) "*"))) @@ -1716,7 +1769,6 @@ so it looks a bit nicer and add pretty symbols to eshell. "×" "✓") ">")))) - (setq eshell-cmpl-ignore-case t eshell-cd-on-directory t eshell-banner-message (concat (shell-command-to-string "figlet eshell") "\n") @@ -1731,10 +1783,9 @@ so it looks a bit nicer and add pretty symbols to eshell. "λ "))) eshell-prompt-regexp "^λ ") - (+dx/create-toggle-function - +shell/toggle-eshell - "*eshell*" - eshell)) + (defun eshell/goto (&rest args) + "Use `read-directory-name' to change directories." + (eshell/cd (list (read-directory-name "Enter directory to go to:"))))) #+end_src ** Elfeed Elfeed is the perfect RSS feed reader, integrated into Emacs |