Wrap-Up

This chapter has covered the most essential aspects of regular expressions that apply to validation of scraped data. There are more advanced aspects of regular expressions that may be useful in other areas. Further review of the PCRE section of the PHP manual is encouraged.

For pattern modifiers, see http://php.net/manual/en/reference.pcre.pattern.modifiers.php.
For pattern syntax, see http://php.net/manual/en/reference.pcre.pattern.syntax.php.
For an excellent book on regular expressions, see “Mastering Regular Expressions,"

ISBN 0596528124.