Match any digit from 0 to 9 using
To match any non-digit, use the upper-case
Use the dot (
.). This will match any character - a letter, digit or whitespace. To use the actual period scape with a backslash
Any alphanumeric character including the underscore. Use
\w. As you'll learn soon, this is the same as
Any non-alphanumeric character is
\W. This is helpful especially for matching punctuations.
\b matches the boundary between a word and a non-word character.
Place each character within square brackets.
Use the square brackets, just like above, with a hat (
^) inside of it.
There is a shortcut to specifying any range of letters or digits. Instead of writing
[abcdefghijklmnopqrstuvwxyz] we can just write write the range between two letter or numbers, separated by a dash (
The whitespace special character
\s will match single type of whitespace - a space, tab, newline or carriage return.
To specify any number of whitespace character use the
Any non-whitespace character will be
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