[\f\t\n\r\v\123\x7F\x{10FFFF}\\\^\$\.\*\+\?\{\}\(\)\[\]\|]

This is a regular expression pattern that matches any of the following characters:

- \f: Form feed
- \t: Tab
- \n: Newline
- \r: Carriage return
- \v: Vertical tab
- \123: Octal escape sequence for the character with ASCII code 83 (i.e., the letter 'S')
- \x7F: Hexadecimal escape sequence for the character with ASCII code 127 (i.e., the "delete" control character)
- \{10FFFF}: Unicode code point escape sequence for the highest possible Unicode character
- \\: Backslash (escaped)
- \^: Caret (escaped)
- \$: Dollar sign (escaped)
- \.: Period (escaped)
- \*: Asterisk (escaped)
- \ : Space (escaped)
- \?: Question mark (escaped)
- \{\}: Curly braces (escaped)
- \(\): Parentheses (escaped)
- \[\]: Square brackets (escaped)
- \|: Pipe (escaped)