Elisp: Lisp Basics
Emacs is possible because of the embedded programing language emacs lisp. Learning a bit emacs lisp will increase your understanding of emacs by a lot.
This chapter teaches the basics of the lisp language core, about syntax, arithmetic operations, string, variable, branch control, loop, function, data structure.
For Emacs Lisp specifics about insert text, delete text, buffer, cursor, coloring text, etc, see Practical Emacs Lisp and Elisp: Create Major Mode
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