In the previous slides we have examined powerful examples of spanning characters; when using the asterisk (*), plus sign (+), or question mark (?).

Regular Expressions includes additional features of spanning characters by indicating the minimum and maximum times an expression can occur; along with specifying that an expression must occur exactly n times.

There have been political wars stating that shorthand notations ought to be avoided. However, whether you use them or not is one thing; you must still be able to interpret regular expression completed by a previous person.

The previous slides have demonstrated the power these features provide. Consider the power added when we can define how to span an expression ourselves.