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Replace standard iOS components with a terminal-inspired design: monospaced typography throughout, flat square borders, Emacs-style modeline header, filetag keyword format (:kw1:kw2:), and custom flat form replacing the iOS Form component. Set Emacs as default theme. Replace non-Emacs demo notes with Emacs ecosystem content and rename screenshots.
60 lines
1.1 KiB
Org Mode
60 lines
1.1 KiB
Org Mode
#+title: Elisp Fundamentals
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#+date: [2024-03-10 Sun]
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#+filetags: :emacs:elisp:
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#+identifier: 20240310T083000
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* Data types
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#+begin_src emacs-lisp
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;; Numbers
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42
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3.14
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;; Strings
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"Hello, Emacs!"
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;; Symbols
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'my-symbol
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;; Lists
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'(1 2 3)
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'(a b c)
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;; Cons cells
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(cons 1 2) ; => (1 . 2)
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#+end_src
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* Defining functions
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#+begin_src emacs-lisp
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(defun greet (name)
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"Return a greeting for NAME."
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(format "Hello, %s!" name))
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(greet "Emacs") ; => "Hello, Emacs!"
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#+end_src
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* let and let*
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#+begin_src emacs-lisp
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(let ((x 10)
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(y 20))
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(+ x y)) ; => 30
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;; let* allows forward references
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(let* ((x 10)
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(y (* x 2)))
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y) ; => 20
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#+end_src
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* Useful built-ins
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| Function | Description |
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|------------------+---------------------------------|
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| car / cdr | Head / tail of a list |
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| mapcar | Map function over list |
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| seq-filter | Filter list by predicate |
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| string-join | Join list of strings |
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| number-to-string | Convert number to string |
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| message | Print to minibuffer |
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