notice that on google maps you can input the address any way you like. as long as it is a valid address...google maps will read it.
In some ruby book I had seen code snippet for something like this, but with phone numbers.
Any ideas how this could be done for addresses?
in language of your choice.
EDIT:
i dont care about a "valid" address. I just want to parse an address. so that 123 fake street, WA, 34223 would be an address and so will 123 fake street WA 34223
it is not trivial task. first you have to have base of all streets, populated places and may me countries (if you want international look up). then try to find each word from input string in each list and try to find matches for all words.
You could create a regular expression that would match each format you want to accept. When one of them matches, you will know how to parse that particular string. If you think about it, there probably aren't more than 10 common formats people will use to type out an address 99.9% of the time.
You can find a commercial solution for this on address-parser.com