BasicGrammar

Matching number

1. Match a number, 0-9

/[0-9]/

/\d/

two。 Match multiple digits

/[0-9]+/

/\d+/

3. Matches a specified number of numbers, such as 1 to 3

/[0-9]{1,3}/

/\d{1,3}/

Matching character

1.\ s Match white space characters, including spaces, line breaks, tab indentation, etc. 2.\ s Matches non-white space characters, as opposed to\ s

3. [\ s\ S] Match all characters 4.\ w Match word characters, equal to [A-Za-z0-9 _] 5.\ W Matches non-word characters, as opposed to\ W

Match string

1. Match everything

/[\s\S]*/
/[\w\W]*/

Matching pattern

1. + The leading character must appear one or n times in the target string

/\d+/

2. * The leading character must appear 0 times or consecutive n times in the target string

/\d*/

3. `` The leading object must appear 0 or 1 times in a row in the target string

/\d?/

4. ^ Locate the first 1 character of the string

/^\d/

5. $

/\d$/

Locate the last 1 character of the string

Greedy matching

1. Greedy mode

/\([\w\W]*\)/.exec("(add (mul 1 2) 3)")

Results: (add (mul 1 2) 3) two。 Non-greedy mode Add it before \)? Number means that if you encounter the first one, it will be over.

/\([\w\W]*?\)/.exec("(add (mul 1 2) 3)")

Result: (add (mul 1 2)