fn decipher(&self, ctext: &str) -> CipherResult {
        input::is_alpha(ctext)?;

        let ctext = ctext.to_ascii_uppercase();
        let key = self.key.as_bytes();

        let ptext = ctext
            .bytes()
            .enumerate()
            .map(move |(i, c)| {
                let y = key[i % key.len()] as usize - 65;
                TABULA_RECTA[y].iter().position(|&j| j == c).unwrap() as u8 + 65
            })
            .collect();

        Ok(String::from_utf8(ptext).unwrap())
    }
/// Deciphers the given ciphertext (a str reference) using the Vigenere cipher
/// and returns the plaintext as a `CipherResult`.
///
/// # Example
/// ```
/// use ciphers::{Cipher, Vigenere};
///
/// let vigenere = Vigenere::new("FORTIFICATION");
///
/// let ptext = vigenere.decipher("ISWXVIBJEXIGGBOCEWKBJEVIGGQS");
/// assert_eq!(ptext.unwrap(), "DEFENDTHEEASTWALLOFTHECASTLE");
/// ```
Deciphers the given ciphertext (a str reference) using the Vigenere cipher
and returns the plaintext as a `CipherResult`.
Deciphers the given ciphertext ( a str reference ) using the Vigenere cipher and returns the plaintext as a ` CipherResult ` .
fn decipher(&self, ctext: &str) -> CipherResult {
        input::is_alpha(ctext)?;
        let ctext = ctext.to_ascii_uppercase();
        let key = self.key.as_bytes();
        let ptext = ctext
            .bytes()
            .enumerate()
            .map(move |(i, c)| {
                let y = key[i % key.len()] as usize - 65;
                TABULA_RECTA[y].iter().position(|&j| j == c).unwrap() as u8 + 65
            })
            .collect();
        Ok(String::from_utf8(ptext).unwrap())
    }
fn decipher ( & self , ctext : & str ) -> CipherResult { input :: is_alpha ( ctext ) ? ; let ctext = ctext . to_ascii_uppercase ( ) ; let key = self . key . as_bytes ( ) ; let ptext = ctext . bytes ( ) . enumerate ( ) . map ( move | ( i , c ) | { let y = key [ i % key . len ( ) ] as usize - 65 ; TABULA_RECTA [ y ] . iter ( ) . position ( | & j | j == c ) . unwrap ( ) as u8 + 65 } ) . collect ( ) ; Ok ( String :: from_utf8 ( ptext ) . unwrap ( ) ) }
Deciphers the given ciphertext (a str reference) using the Vigenere cipher
and returns the plaintext as a `CipherResult`.
Deciphers the given ciphertext ( a str reference ) using the Vigenere cipher and returns the plaintext as a ` CipherResult ` .
&self
ctext
&str
&self
ctext
&str
example
```
use ciphers::{Cipher, Vigenere}.

let vigenere = Vigenere::new("FORTIFICATION").

let ptext = vigenere.decipher("ISWXVIBJEXIGGBOCEWKBJEVIGGQS");
assert_eq!(ptext.unwrap(), "DEFENDTHEEASTWALLOFTHECASTLE");
```
` ` ` use ciphers :: { Cipher Vigenere } . let vigenere = Vigenere :: new ( " FORTIFICATION " ) . let ptext = vigenere . decipher ( " ISWXVIBJEXIGGBOCEWKBJEVIGGQS " ) ; assert_eq! ( ptext . unwrap () " DEFENDTHEEASTWALLOFTHECASTLE " ) ; ` ` `