Fetch all lower case English language words from Wiktionary

WiktionaryFetcher.swift

import Foundation

extension String {
    
    func stringsBetween(fromTag: String, and toTag: String) -> [String]? {
        
        let fromTagLen = countElements(fromTag)
        let toTagLen = countElements(toTag)
        var strings: [String]?
        
        var startIndex = rangeOfString(fromTag, options: nil, range: rangeOfString(self))?.startIndex
        while startIndex != nil {
            
            for i in 0..<fromTagLen {
                startIndex = startIndex!.successor()
            }
            
            var testRange = Range(start: startIndex!, end: self.endIndex)
            var endIndex = rangeOfString(toTag, options: nil, range: testRange)?.startIndex
            
            if endIndex != nil {
                let string = substringWithRange(Range(start: startIndex!, end: endIndex!))
                if strings == nil {
                    strings = [string]
                } else {
                    strings?.append(string)
                }
                for i in 0..<toTagLen {
                    endIndex = endIndex!.successor()
                }
                testRange = Range(start: endIndex!, end: self.endIndex)
            } else {
                return strings
            }
            
            startIndex = rangeOfString(fromTag, options: nil, range: testRange)?.startIndex
        }
        
        return strings
    }
    
    func isValidDictionaryString() -> Bool {
        let nonLower = NSCharacterSet.lowercaseLetterCharacterSet().invertedSet
        return rangeOfCharacterFromSet(nonLower) == nil
    }
}

let baseURL = NSURL(string: "http://en.wiktionary.org/wiki/Index:English/")
let letters = Array("abcdefghijklmnopqrstuvwxyz")
let numbers = Array("12")
var error: NSError?
for letter in letters {
    for number in numbers {
        if let URL = baseURL?.URLByAppendingPathComponent(String(letter) + String(number)) {
            if let response = String(contentsOfURL: URL, encoding: NSUTF8StringEncoding, error: &error) {
                
                if let olStrings = response.stringsBetween("<ol>", and: "</ol>") {
                    for olString in olStrings {
                        if let liStrings = olString.stringsBetween("<li>", and: "</li>") {
                            for liString in liStrings {
                                if let wordStrings = liString.stringsBetween("<a href=\"/wiki/", and: "\" title") {
                                    for wordString in wordStrings {
                                        
                                        if wordString.isValidDictionaryString() {
                                            println("\(wordString)")
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }
}