Build, test, and debug regular expressions
Matches C/C++ style pointer or reference declarations by capturing a type name (word characters), optional whitespace, a sequence of asterisks/ampersands, and a single-character variable identifier. Useful for refactoring code style (e.g., converting 'int *p' to 'int* p') and detecting declarations with unusual spacing. The 'gm' flags apply matching across multiple lines.