Expose words and add Display to Error. (#10)

* Expose words and add Display to Error.

* Update readme.

README.md

@@ -2,7 +2,7 @@
 Parity Brain Wallets wordlist library
 
 
-[Rust Documentation](https://docs.rs/parity-wordlist/1.1.0/parity_wordlist/)
+[Rust Documentation](https://docs.rs/parity-wordlist/)
 
 
 # RUST

src/lib.rs

@@ -24,12 +24,14 @@ extern crate lazy_static;
 extern crate itertools;
 extern crate rand;
 
+use std::fmt;
 use std::collections::HashSet;
 use itertools::Itertools;
 use rand::{Rng, OsRng};
 
+/// The list of dictionary words.
 // the wordlist JSON also happens to be valid Rust syntax for an array constant.
-const WORDS: &'static [&'static str] = &include!("../res/wordlist.json");
+pub const WORDS: &'static [&'static str] = &include!("../res/wordlist.json");
 
 /// Generate a string which is a random phrase of a number of lowercase words.
 ///
@@ -50,6 +52,15 @@ pub enum Error {
 	WordNotFromDictionary(String),
 }
 
+impl fmt::Display for Error {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            Error::PhraseTooShort(len) => writeln!(fmt, "The phrase is too short ({})", len),
+            Error::WordNotFromDictionary(ref word) => writeln!(fmt, "The word '{}' does not come from the dictionary.", word),
+        }
+    }
+}
+
 /// Validates given phrase and checks if:
 /// 1. All the words are coming from the dictionary.
 /// 2. There are at least `expected_no_of_words` in the phrase.