Build, test, and debug regular expressions
Matches capitalized personal names in American style, such as 'John' or 'John Smith', where each segment starts with an uppercase letter followed by lowercase letters, dots, or apostrophes. A negative lookahead at the start rejects strings beginning with special symbols followed by a lowercase letter and digit, and the trailing space requirement helps match names embedded within larger text. The multiline and global flags allow scanning for all name occurrences across multiple lines of input.