some cleanup

src/main.rs

@@ -1,10 +1,8 @@
 #[macro_use]
 extern crate pest_derive;
-use pest::iterators::Pair;
 use pest::Parser;
 use serde::de;
 use serde::de::value::MapDeserializer;
-use serde::de::DeserializeOwned;
 use serde::forward_to_deserialize_any;
 use serde::Deserialize;
 mod error;
@@ -14,11 +12,11 @@ use error::MpdResult;
 #[grammar = "response.pest"]
 struct MpdParser;
 
-struct MPDeserializer<'de, Iter: Iterator<Item = (String, String)>> {
+struct MPDeserializer<'de, Iter: Iterator<Item = (&'de str, &'de str)>> {
     inner: MapDeserializer<'de, Iter, error::Error>,
 }
 
-impl<'de, Iter: Iterator<Item = (String, String)>> de::Deserializer<'de>
+impl<'de, Iter: Iterator<Item = (&'de str, &'de str)>> de::Deserializer<'de>
     for MPDeserializer<'de, Iter>
 {
     type Error = error::Error;
@@ -45,15 +43,12 @@ impl<'de, Iter: Iterator<Item = (String, String)>> de::Deserializer<'de>
 }
 
 #[derive(Debug, Deserialize)]
+#[serde(rename_all = "PascalCase")]
 struct Song {
-    Title: String,
-    Artist: String,
+    title: String,
+    artist: String,
 }
 
-const input_var: &str = "Title: A song 星
-Artist: A name
-OK mpd 0.21.23";
-
 fn main() {
     /*
     let parsed = MpdParser::parse(Rule::response, input)
@@ -75,30 +70,32 @@ fn main() {
         let d = Song::deserialize(&mut deser);
         println!("{:?}", d);
     */
+    let input_var: &str = "Title: A song 星
+Artist: A name
+OK mpd 0.21.23";
+
     let mut map = std::collections::HashMap::new();
     let parser = MpdParser::parse(Rule::response, input_var)
         .unwrap()
         .next()
         .unwrap();
-    for pair in parser.into_inner() {
-        let rule = pair.as_rule();
-        match rule {
+    for line in parser.into_inner() {
+        match line.as_rule() {
             Rule::kv => {
-                let mut fields = pair.into_inner();
+                let mut fields = line.into_inner();
                 map.insert(
-                    fields.next().unwrap().as_str().to_string(),
-                    fields.next().unwrap().as_str().to_string(),
+                    fields.next().unwrap().as_str(),
+                    fields.next().unwrap().as_str(),
                 );
             }
-            Rule::ok => (),
+            Rule::ok => break,
             Rule::err => panic!("received error response"),
             _ => unreachable!(),
         }
     }
-    // ::<'_, _, Song>
     dbg!(&map);
     let deser = MPDeserializer {
-        inner: serde::de::value::MapDeserializer::new(map.into_iter()),
+        inner: MapDeserializer::new(map.into_iter()),
     };
     let s = Song::deserialize(deser);
     println!("{:?}", s);