Removed various bits of unused code

src/tokens.rs

@@ -58,28 +58,8 @@ pub struct Token {
 }
 
 impl Token {
-    /// Check whether a token corresponds to a litteral value.
-    pub fn is_litteral(&self) -> bool {
-        matches!(
-            self.token_type,
-            TokenType::True
-                | TokenType::False
-                | TokenType::Nil
-                | TokenType::String(_)
-                | TokenType::Number(_)
-        )
-    }
-
     /// Check whether a token is an identifier.
     pub fn is_identifier(&self) -> bool {
         matches!(self.token_type, TokenType::Identifier(_))
     }
-
-    /// Get the name from an identifier token, returning an error otherwise.
-    pub fn as_identifier(&self) -> Result<&str, &'static str> {
-        match &self.token_type {
-            TokenType::Identifier(name) => Ok(name),
-            _ => Err("token is not an identifier"),
-        }
-    }
 }