Elisp programming 2: Atom, symbol, space, comment

Atom

The inseparable elements in the list are called atom, such as numbers, words, and operator numbers in the previous article.

A list can have only one element or no element. Empty list is written as (), which is a special list because it is also regarded as an atom.

Array (array) is also an atom, but can be divided into multiple parts.

The string enclosed in double quotation marks is also an atom, which has a string name.

Symbol

Symbol is an object that contains attributes such as name, value, and function. Some functions can access your attributes, such as symbol_value.

When you define a variable, you actually create a symbol object, and then place the value of the variable to the value attribute of the symbol object.

For more information, see this article (recommended): http://www.cppblog.com/kevinlynx/archive/2011/03/22/142462.html

Space and line feed

Extra spaces are automatically removed. line breaks are only used to facilitate reading and are also removed.

Note

; Starts with a comment.

However, two consecutive semicolons are often used. For example, my. emacs file contains

;;------------------------------------------------------------------------------;; Input method for Chinese;;------------------------------------------------------------------------------;;sudo apt-get install ibus-el(require 'ibus)(add-hook 'after-init-hook 'ibus-mode-on)