Custom searches, like interactively searching palindromes

[Karan Bathla <karan_goku@yahoo.com>]

Hi

I would like to know how one can interactively search for patterns that are not captured by regexes, like palindromes.

One approach would be to use \, to embed a lisp function, like it's availabe in regex-replace. Is it easy to modify existing functions (or make new ones using the ones available) to do this?

Or maybe something like (check-for-pattern palindrome), where palindrome is a function that takes a string and returns true if that string is palindrome. The function check-for-pattern does the search interactively feeding new string in the buffer to palindrome and highlighting them if they match. The problem I am facing here is writing the check-for-pattern function using the existing search functions.

Any other ways to do it ?

Thanks 
Karan