> - given regexes A and B we can construct the new regex AB that matches first the regex A followed by B
> - given regexes A and B we can construct A|B that matches A or B
Concatenation and alternation is not what one typically imagines when they utter the word composition (unless you expect me to understand "composition over inheritance" to mean actually "just use two classes instead of one").
Concatenation and alternation is not what one typically imagines when they utter the word composition (unless you expect me to understand "composition over inheritance" to mean actually "just use two classes instead of one").