better & faster parsing of toml

src/main.rs

@@ -17,7 +17,6 @@
 
 use std::env;
 use std::fs::File;
-use std::io;
 use std::io::Read;
 use std::path::Path;
 use std::process;
@@ -27,44 +26,52 @@ use toml::Value;
 fn main() {
   let mut arguments: Vec<String> = env::args().collect();
   let argv0 = arguments.remove(0);
+  if arguments[1].is_empty() {
+    println!("Usage: {} [table...].[value] [file...]", argv0);
+    process::exit(64); // sysexits(3) EX_USAGE
+  }
   let input = &arguments[1];
   let mut content = String::new();
   
-  let mut file = Path::new(&input);
+  let file = Path::new(&input);
   if file.is_file() {
     File::open(file).unwrap().read_to_string(&mut content).unwrap();
   } else { content = input.to_string(); }
 
-  let keyval: Vec<&str> = arguments[0].split(".").collect();
+  let tabkey: Vec<&str> = arguments[0].split(".").collect();
-  let toml = content.parse::<Value>().unwrap();
+  let mut root = content.parse::<Value>().unwrap();
   
-  let mut table = &toml;
+  let mut out = String::new();
-  if ! keyval[0].is_empty() {
+  let mut valiter = tabkey.iter().peekable();
-    match toml.get(keyval[0]) {
+  
-      Some(table) => {
+  while let Some(item) = valiter.next() {
-        if keyval[1].is_empty() {
+    match root.get(item) {
-          println!("{}", table.as_str().unwrap());
+      Some(value) => {
-        } else {
+        match value {
-          match table.get(keyval[1]) {
+          // TODO: Implement other type parsing
-            Some(value) => {
+          Value::Array(_array) => {}, 
-              let out = value
+          Value::Boolean(_boolean) => {}, 
-                .as_str()
+          Value::Datetime(_datetime) => {}, 
-                .unwrap()
+          Value::Float(_float) => {},
-                .trim_start_matches('"')
+          Value::Integer(_int) => {},
-                .trim_end_matches('"');
+          Value::String(string) => {
-              println!("{}", out);
+            match valiter.peek() {
-            },
+              Some(next) => {
-            None => {
+                println!("{}: {}: Not a table.", argv0, item);
-              eprintln!("{}: {}: No such key.", argv0, keyval[1]);
+                process::exit(65); // sysexits(3) EX_DATAERR
-              process::exit(1);
+              },
-            },
+              None => out.push_str(string.as_str()),
-          };
+            };
-        }
+            break
+          }
+          Value::Table(table) => root = toml::Value::Table(table.to_owned()),
+        };
       },
       None => {
-        eprintln!("{}: {}: No such table.", argv0, keyval[0]);
+        println!("{}: {}: No such table or key.", argv0, item);
-        process::exit(1);
+        process::exit(65); // sysexits(3) EX_DATAERR
       },
     };
   }
+  println!("{}", out);
 }