Wouldn't it be good to add the use of parentheses using posix ? It's useful and rarely documented
<literal>substring('Thomas', '...$')</literal>
+ <literal>substring('Email: johnjohn@mymail.com, Name: John' from '@(.*), Name')</literal>
Agreed. A second example using () would be good here.
Was pondering explaining the "no parentheses" case here; but for someone familiar with PREs the behavior is obvious and everyone else has the link needed to learn what is happening.
