Removing some mutable fields in libstd

Author: alexcrichton

src/libstd/arc.rs

@@ -259,7 +259,7 @@ struct RWARCInner<T> { lock: RWlock, failed: bool, data: T }
  */
 struct RWARC<T> {
     x: SharedMutableState<RWARCInner<T>>,
-    mut cant_nest: ()
+    cant_nest: ()
 }
 
 /// Create a reader/writer ARC with the supplied data.

src/libstd/json.rs

@@ -360,9 +360,9 @@ pub fn to_pretty_str(json: &Json) -> ~str {
 
 pub struct Parser {
     priv rdr: @io::Reader,
-    priv mut ch: char,
-    priv mut line: uint,
-    priv mut col: uint,
+    priv ch: char,
+    priv line: uint,
+    priv col: uint,
 }
 
 /// Decode a json value from an io::reader
@@ -376,7 +376,7 @@ pub fn Parser(rdr: @io::Reader) -> Parser {
 }
 
 pub impl Parser {
-    fn parse(&self) -> Result<Json, Error> {
+    fn parse(&mut self) -> Result<Json, Error> {
         match self.parse_value() {
           Ok(value) => {
             // Skip trailing whitespaces.
@@ -396,7 +396,7 @@ pub impl Parser {
 priv impl Parser {
     fn eof(&self) -> bool { self.ch == -1 as char }
 
-    fn bump(&self) {
+    fn bump(&mut self) {
         self.ch = self.rdr.read_char();
 
         if self.ch == '\n' {
@@ -407,7 +407,7 @@ priv impl Parser {
         }
     }
 
-    fn next_char(&self) -> char {
+    fn next_char(&mut self) -> char {
         self.bump();
         self.ch
     }
@@ -416,7 +416,7 @@ priv impl Parser {
         Err(Error { line: self.line, col: self.col, msg: @msg })
     }
 
-    fn parse_value(&self) -> Result<Json, Error> {
+    fn parse_value(&mut self) -> Result<Json, Error> {
         self.parse_whitespace();
 
         if self.eof() { return self.error(~"EOF while parsing value"); }
@@ -437,11 +437,11 @@ priv impl Parser {
         }
     }
 
-    fn parse_whitespace(&self) {
+    fn parse_whitespace(&mut self) {
         while char::is_whitespace(self.ch) { self.bump(); }
     }
 
-    fn parse_ident(&self, ident: &str, value: Json) -> Result<Json, Error> {
+    fn parse_ident(&mut self, ident: &str, value: Json) -> Result<Json, Error> {
         if str::all(ident, |c| c == self.next_char()) {
             self.bump();
             Ok(value)
@@ -450,7 +450,7 @@ priv impl Parser {
         }
     }
 
-    fn parse_number(&self) -> Result<Json, Error> {
+    fn parse_number(&mut self) -> Result<Json, Error> {
         let mut neg = 1f;
 
         if self.ch == '-' {
@@ -480,7 +480,7 @@ priv impl Parser {
         Ok(Number(neg * res))
     }
 
-    fn parse_integer(&self) -> Result<float, Error> {
+    fn parse_integer(&mut self) -> Result<float, Error> {
         let mut res = 0f;
 
         match self.ch {
@@ -512,7 +512,7 @@ priv impl Parser {
         Ok(res)
     }
 
-    fn parse_decimal(&self, res: float) -> Result<float, Error> {
+    fn parse_decimal(&mut self, res: float) -> Result<float, Error> {
         self.bump();
 
         // Make sure a digit follows the decimal place.
@@ -538,10 +538,9 @@ priv impl Parser {
         Ok(res)
     }
 
-    fn parse_exponent(&self, res: float) -> Result<float, Error> {
+    fn parse_exponent(&mut self, mut res: float) -> Result<float, Error> {
         self.bump();
 
-        let mut res = res;
         let mut exp = 0u;
         let mut neg_exp = false;
 
@@ -579,7 +578,7 @@ priv impl Parser {
         Ok(res)
     }
 
-    fn parse_str(&self) -> Result<~str, Error> {
+    fn parse_str(&mut self) -> Result<~str, Error> {
         let mut escape = false;
         let mut res = ~"";
 
@@ -643,7 +642,7 @@ priv impl Parser {
         self.error(~"EOF while parsing string")
     }
 
-    fn parse_list(&self) -> Result<Json, Error> {
+    fn parse_list(&mut self) -> Result<Json, Error> {
         self.bump();
         self.parse_whitespace();
 
@@ -673,7 +672,7 @@ priv impl Parser {
         };
     }
 
-    fn parse_object(&self) -> Result<Json, Error> {
+    fn parse_object(&mut self) -> Result<Json, Error> {
         self.bump();
         self.parse_whitespace();
 
@@ -726,7 +725,8 @@ priv impl Parser {
 
 /// Decodes a json value from an @io::Reader
 pub fn from_reader(rdr: @io::Reader) -> Result<Json, Error> {
-    Parser(rdr).parse()
+    let mut parser = Parser(rdr);
+    parser.parse()
 }
 
 /// Decodes a json value from a string

src/libstd/num/complex.rs

@@ -239,7 +239,6 @@ mod test {
 
     mod arith {
         use super::*;
-        use super::super::*;
         use core::num::Zero;
 
         #[test]

src/libstd/rope.rs

@@ -455,7 +455,7 @@ pub mod iterator {
               node::Content(x) => return node::leaf_iterator::start(x)
             }
         }
-        pub fn next(it: &node::leaf_iterator::T) -> Option<node::Leaf> {
+        pub fn next(it: &mut node::leaf_iterator::T) -> Option<node::Leaf> {
             return node::leaf_iterator::next(it);
         }
     }
@@ -470,7 +470,7 @@ pub mod iterator {
               node::Content(x) => return node::char_iterator::start(x)
             }
         }
-        pub fn next(it: &node::char_iterator::T) -> Option<char> {
+        pub fn next(it: &mut node::char_iterator::T) -> Option<char> {
             return node::char_iterator::next(it)
         }
     }
@@ -832,9 +832,9 @@ pub mod node {
         unsafe {
             let mut buf = vec::from_elem(byte_len(node), 0);
             let mut offset = 0u;//Current position in the buffer
-            let it = leaf_iterator::start(node);
+            let mut it = leaf_iterator::start(node);
             loop {
-                match (leaf_iterator::next(&it)) {
+                match leaf_iterator::next(&mut it) {
                   option::None => break,
                   option::Some(x) => {
                     //FIXME (#2744): Replace with memcpy or something similar
@@ -896,9 +896,9 @@ pub mod node {
         if height(node) < hint_max_node_height { return option::None; }
         //1. Gather all leaves as a forest
         let mut forest = ~[];
-        let it = leaf_iterator::start(node);
+        let mut it = leaf_iterator::start(node);
         loop {
-            match (leaf_iterator::next(&it)) {
+            match leaf_iterator::next(&mut it) {
               option::None    => break,
               option::Some(x) => forest.push(@Leaf(x))
             }
@@ -1058,11 +1058,12 @@ pub mod node {
     }
 
     pub fn cmp(a: @Node, b: @Node) -> int {
-        let ita = char_iterator::start(a);
-        let itb = char_iterator::start(b);
+        let mut ita = char_iterator::start(a);
+        let mut itb = char_iterator::start(b);
         let mut result = 0;
         while result == 0 {
-            match ((char_iterator::next(&ita), char_iterator::next(&itb))) {
+            match (char_iterator::next(&mut ita), char_iterator::next(&mut itb))
+            {
               (option::None, option::None) => break,
               (option::Some(chara), option::Some(charb)) => {
                 result = char::cmp(chara, charb);
@@ -1131,9 +1132,7 @@ pub mod node {
      * proportional to the height of the rope + the (bounded)
      * length of the largest leaf.
      */
-    pub fn char_at(node: @Node, pos: uint) -> char {
-        let mut node    = node;
-        let mut pos     = pos;
+    pub fn char_at(mut node: @Node, mut pos: uint) -> char {
         loop {
             match *node {
               Leaf(x) => return str::char_at(*x.content, pos),
@@ -1154,8 +1153,8 @@ pub mod node {
         use core::vec;
 
         pub struct T {
-            mut stack: ~[@Node],
-            mut stackpos: int,
+            stack: ~[@Node],
+            stackpos: int,
         }
 
         pub fn empty() -> T {
@@ -1171,7 +1170,7 @@ pub mod node {
             }
         }
 
-        pub fn next(it: &T) -> Option<Leaf> {
+        pub fn next(it: &mut T) -> Option<Leaf> {
             if it.stackpos < 0 { return option::None; }
             loop {
                 let current = it.stack[it.stackpos];
@@ -1199,8 +1198,8 @@ pub mod node {
 
         pub struct T {
             leaf_iterator: leaf_iterator::T,
-            mut leaf:  Option<Leaf>,
-            mut leaf_byte_pos: uint,
+            leaf:  Option<Leaf>,
+            leaf_byte_pos: uint,
         }
 
         pub fn start(node: @Node) -> T {
@@ -1219,13 +1218,13 @@ pub mod node {
             }
         }
 
-        pub fn next(it: &T) -> Option<char> {
+        pub fn next(it: &mut T) -> Option<char> {
             loop {
-                match (get_current_or_next_leaf(it)) {
+                match get_current_or_next_leaf(it) {
                   option::None => return option::None,
                   option::Some(_) => {
                     let next_char = get_next_char_in_leaf(it);
-                    match (next_char) {
+                    match next_char {
                       option::None => loop,
                       option::Some(_) => return next_char
                     }
@@ -1234,30 +1233,30 @@ pub mod node {
             };
         }
 
-        pub fn get_current_or_next_leaf(it: &T) -> Option<Leaf> {
-            match ((*it).leaf) {
-              option::Some(_) => return (*it).leaf,
+        pub fn get_current_or_next_leaf(it: &mut T) -> Option<Leaf> {
+            match it.leaf {
+              option::Some(_) => return it.leaf,
               option::None => {
-                let next = leaf_iterator::next(&((*it).leaf_iterator));
-                match (next) {
+                let next = leaf_iterator::next(&mut it.leaf_iterator);
+                match next {
                   option::None => return option::None,
                   option::Some(_) => {
-                    (*it).leaf          = next;
-                    (*it).leaf_byte_pos = 0u;
+                    it.leaf          = next;
+                    it.leaf_byte_pos = 0u;
                     return next;
                   }
                 }
               }
             }
         }
 
-        pub fn get_next_char_in_leaf(it: &T) -> Option<char> {
-            match copy (*it).leaf {
+        pub fn get_next_char_in_leaf(it: &mut T) -> Option<char> {
+            match copy it.leaf {
               option::None => return option::None,
               option::Some(aleaf) => {
-                if (*it).leaf_byte_pos >= aleaf.byte_len {
+                if it.leaf_byte_pos >= aleaf.byte_len {
                     //We are actually past the end of the leaf
-                    (*it).leaf = option::None;
+                    it.leaf = option::None;
                     return option::None
                 } else {
                     let range =
@@ -1342,11 +1341,11 @@ mod tests {
         assert!(rope_to_string(r) == *sample);
 
         let mut string_iter = 0u;
-        let string_len  = str::len(*sample);
-        let rope_iter   = iterator::char::start(r);
-        let mut equal   = true;
+        let string_len = str::len(*sample);
+        let mut rope_iter = iterator::char::start(r);
+        let mut equal = true;
         while equal {
-            match (node::char_iterator::next(&rope_iter)) {
+            match (node::char_iterator::next(&mut rope_iter)) {
               option::None => {
                 if string_iter < string_len {
                     equal = false;
@@ -1376,9 +1375,9 @@ mod tests {
         let r      = of_str(sample);
 
         let mut len = 0u;
-        let it  = iterator::char::start(r);
+        let mut it  = iterator::char::start(r);
         loop {
-            match (node::char_iterator::next(&it)) {
+            match (node::char_iterator::next(&mut it)) {
               option::None => break,
               option::Some(_) => len += 1u
             }

src/libstd/sync.rs

@@ -72,7 +72,7 @@ fn broadcast_waitqueue(q: &Waitqueue) -> uint {
 // The building-block used to make semaphores, mutexes, and rwlocks.
 #[doc(hidden)]
 struct SemInner<Q> {
-    mut count: int,
+    count: int,
     waiters:   Waitqueue,
     // Can be either unit or another waitqueue. Some sems shouldn't come with
     // a condition variable attached, others should.
@@ -729,7 +729,6 @@ mod tests {
 
     use core::cast;
     use core::cell::Cell;
-    use core::option;
     use core::ptr;
     use core::result;
     use core::task;

src/libstd/task_pool.rs

@@ -26,8 +26,7 @@ enum Msg<T> {
 
 pub struct TaskPool<T> {
     channels: ~[Chan<Msg<T>>],
-    mut next_index: uint,
-
+    next_index: uint,
 }
 
 #[unsafe_destructor]
@@ -84,7 +83,7 @@ pub impl<T> TaskPool<T> {
 
     /// Executes the function `f` on a task in the pool. The function
     /// receives a reference to the local data returned by the `init_fn`.
-    fn execute(&self, f: ~fn(&T)) {
+    fn execute(&mut self, f: ~fn(&T)) {
         self.channels[self.next_index].send(Execute(f));
         self.next_index += 1;
         if self.next_index == self.channels.len() { self.next_index = 0; }
@@ -97,7 +96,7 @@ fn test_task_pool() {
         let g: ~fn(uint) -> uint = |i| i;
         g
     };
-    let pool = TaskPool::new(4, Some(SingleThreaded), f);
+    let mut pool = TaskPool::new(4, Some(SingleThreaded), f);
     for 8.times {
         pool.execute(|i| io::println(fmt!("Hello from thread %u!", *i)));
     }