Regular expressions in jquery analysis regular basis _ regular expressions

quickexpr =/^ (?: [^<]* (<[\w\W]+>) [^>]*$|# ([\w\-]+) $)/
(?:...) Represents a non-capture type

[^<] indicates that it starts with "<" and contains 0 or more ' < ' brackets

(<[\w\W]+>) is a catch type that starts with ' <> ' and contains one or more characters in the middle

$ indicates the end of a character

(# ([\w\-]+)) means a catch type, with ' # ' numbers and strings, numbers, _, and-

Rnotwhite =/\s/
\s represents a symbol other than a blank character

Trimleft =/^\s+/trimright =/\s+$/
The left and right edges of the blank. S is a blank character. ^ prefix denotes string start, $ suffix indicates end of string

Rdigit =/\d/
Indicates a number

Rsingletag =/^< (\w+) \s*\/?> (?:<\/\1>)? $/
^< (\w+) \s*\/?>
The expression starts with ' < ', contains one to many characters, and 0 to multiple blanks, 0 or one '/' and ' > ' End,

(?:<\/\1>)? $

Indicates that the end of the first capture exists or does not exist