JavaScript regular expressions provide Unicode character classses and Unicode property escapes for matching characters based on their Unicode values and Unicode properties respectively. When using Unicode property escapes like `+\p{Alpha}+` without the `+u+` flag, the regular expression will not match alphabetic characters but rather the `+'\p{Alpha}+'` string literal, which is likely a mistake. This rules raises an issue when Unicode character classses and Unicode property escapes are used without the `+u+` flag. == Noncompliant Code Example ---- /\u{1234}/ /\p{Alpha}/ ---- == Compliant Solution ---- /\u{1234}/u /\p{Alpha}/u ----