Disallows the use ascii control characters in regular expressions Control characters are invisible characters in the ASCII range of 0-31. It is uncommon to use these in a regular expression and more often it is a mistake in the regular expression. ### Invalid: ```typescript // Examples using ASCII (31) Carriage Return (hex x0d) const pattern1 = /\x0d/; const pattern2 = /\u000d/; const pattern3 = new RegExp("\\x0d"); const pattern4 = new RegExp("\\u000d"); ``` ### Valid: ```typescript // Examples using ASCII (32) Space (hex x20) const pattern1 = /\x20/; const pattern2 = /\u0020/; const pattern3 = new RegExp("\\x20"); const pattern4 = new RegExp("\\u0020"); ```