How do I analyze a PCRE pattern?

How do I analyze a PCRE pattern?

References

Reference NO 1

http://stackoverflow.com/questions/13658979/how-do-i-analyze-a-pcre-pattern

Reference NO 2

http://www.cs.washington.edu/education/courses/cse190m/12sp/cheat-sheets/php-regex-cheat-sheet.pdf

Reference NO 3

http://php.net/manual/en/reference.pcre.pattern.modifiers.php

Reference NO 4

http://regex.larsolavtorvik.com/

Reference NO 5

https://github.com/mscdex/node-pcre

Reference NO 6

http://www.regular-expressions.info/pcre.html

Reference NO 7

http://www.phpfreaks.com/tutorial/regular-expressions-part1---basic-syntax

Reference NO 8

http://scholar.lib.vt.edu/manuals/php3.0.6/pcre.pattern.modifiers.html