Documentation / Regular Expressions / Alternative |
Alternative |
Alternative matches one of the specified patterns, which are separated by |.
| (http|ftp):// | http:// or ftp:// |
| table|tr|td | table, tr, or td |
| (https?|ftp):// | http://, https://, or ftp:// |
You often have to use the parentheses for grouping, as shown in the first example. Without parentheses, this example will be interpreted as “http or ftp://”.