Merge pull request #4278 from cpeterso/incoming-pure-functions

Mark some more core and std functions as pure

src/libcore/dvec.rs

@@ -67,17 +67,17 @@ pub pure fn DVec<A>() -> DVec<A> {
 }
 
 /// Creates a new dvec with a single element
-pub fn from_elem<A>(e: A) -> DVec<A> {
+pub pure fn from_elem<A>(e: A) -> DVec<A> {
     DVec {mut data: ~[move e]}
 }
 
 /// Creates a new dvec with the contents of a vector
-pub fn from_vec<A>(v: ~[A]) -> DVec<A> {
+pub pure fn from_vec<A>(v: ~[A]) -> DVec<A> {
     DVec {mut data: move v}
 }
 
 /// Consumes the vector and returns its contents
-pub fn unwrap<A>(d: DVec<A>) -> ~[A] {
+pub pure fn unwrap<A>(d: DVec<A>) -> ~[A] {
     let DVec {data: v} = move d;
     move v
 }

src/libcore/float.rs

@@ -188,7 +188,7 @@ pub pure fn to_str_common(num: float, digits: uint, exact: bool) -> ~str {
  * * num - The float value
  * * digits - The number of significant digits
  */
-pub fn to_str_exact(num: float, digits: uint) -> ~str {
+pub pure fn to_str_exact(num: float, digits: uint) -> ~str {
     to_str_common(num, digits, true)
 }
 
@@ -238,7 +238,7 @@ pub pure fn to_str(num: float, digits: uint) -> ~str {
  * `none` if the string did not represent a valid number.  Otherwise,
  * `Some(n)` where `n` is the floating-point number represented by `[num]`.
  */
-pub fn from_str(num: &str) -> Option<float> {
+pub pure fn from_str(num: &str) -> Option<float> {
    if num == "inf" {
        return Some(infinity as float);
    } else if num == "-inf" {

src/libcore/int-template/int.rs

@@ -17,12 +17,12 @@ mod inst {
     pub const bits: uint = uint::bits;
 
     /// Returns `base` raised to the power of `exponent`
-    pub fn pow(base: int, exponent: uint) -> int {
+    pub pure fn pow(base: int, exponent: uint) -> int {
         if exponent == 0u {
             //Not mathemtically true if ~[base == 0]
             return 1;
         }
-        if base     == 0  { return 0; }
+        if base == 0 { return 0; }
         let mut my_pow  = exponent;
         let mut acc     = 1;
         let mut multiplier = base;

src/libcore/ptr.rs

@@ -170,13 +170,13 @@ pub pure fn to_mut_unsafe_ptr<T>(thing: &mut T) -> *mut T {
   (I couldn't think of a cutesy name for this one.)
 */
 #[inline(always)]
-pub fn to_uint<T>(thing: &T) -> uint unsafe {
+pub pure fn to_uint<T>(thing: &T) -> uint unsafe {
     cast::reinterpret_cast(&thing)
 }
 
 /// Determine if two borrowed pointers point to the same thing.
 #[inline(always)]
-pub fn ref_eq<T>(thing: &a/T, other: &b/T) -> bool {
+pub pure fn ref_eq<T>(thing: &a/T, other: &b/T) -> bool {
     to_uint(thing) == to_uint(other)
 }
 

src/libcore/rand.rs

@@ -309,12 +309,12 @@ impl XorShiftState: Rng {
     }
 }
 
-pub fn xorshift() -> Rng {
+pub pure fn xorshift() -> Rng {
     // constants taken from http://en.wikipedia.org/wiki/Xorshift
     seeded_xorshift(123456789u32, 362436069u32, 521288629u32, 88675123u32)
 }
 
-pub fn seeded_xorshift(x: u32, y: u32, z: u32, w: u32) -> Rng {
+pub pure fn seeded_xorshift(x: u32, y: u32, z: u32, w: u32) -> Rng {
     {mut x: x, mut y: y, mut z: z, mut w: w} as Rng
 }
 

src/libcore/str.rs

@@ -214,7 +214,7 @@ pub pure fn connect(v: &[~str], sep: &str) -> ~str {
 }
 
 /// Given a string, make a new string with repeated copies of it
-pub fn repeat(ss: &str, nn: uint) -> ~str {
+pub pure fn repeat(ss: &str, nn: uint) -> ~str {
     let mut acc = ~"";
     for nn.times { acc += ss; }
     acc
@@ -1684,9 +1684,7 @@ pub struct CharRange {
  *
  * This function can be used to iterate over a unicode string in reverse.
  */
-pure fn char_range_at_reverse(ss: &str, start: uint)
-    -> CharRange {
-
+pure fn char_range_at_reverse(ss: &str, start: uint) -> CharRange {
     let mut prev = start;
 
     // while there is a previous byte == 10......

src/libcore/uint-template/uint.rs

@@ -104,7 +104,7 @@ mod inst {
 
     /// Returns the smallest power of 2 greater than or equal to `n`
     #[inline(always)]
-    pub fn next_power_of_two(n: uint) -> uint {
+    pub pure fn next_power_of_two(n: uint) -> uint {
         let halfbits: uint = sys::size_of::<uint>() * 4u;
         let mut tmp: uint = n - 1u;
         let mut shift: uint = 1u;

src/libstd/arena.rs

@@ -95,7 +95,7 @@ pub fn Arena() -> Arena {
 }
 
 #[inline(always)]
-fn round_up_to(base: uint, align: uint) -> uint {
+pure fn round_up_to(base: uint, align: uint) -> uint {
     (base + (align - 1)) & !(align - 1)
 }
 

src/libstd/c_vec.rs

@@ -135,7 +135,7 @@ pub fn set<T: Copy>(t: CVec<T>, ofs: uint, v: T) {
  */
 
 /// Returns the length of the vector
-pub fn len<T>(t: CVec<T>) -> uint {
+pub pure fn len<T>(t: CVec<T>) -> uint {
     return (*t).len;
 }
 

src/libstd/list.rs

@@ -22,8 +22,8 @@ pub enum List<T> {
     Nil,
 }
 
-/// Cregate a list from a vector
-pub fn from_vec<T: Copy>(v: &[T]) -> @List<T> {
+/// Create a list from a vector
+pub pure fn from_vec<T: Copy>(v: &[T]) -> @List<T> {
     vec::foldr(v, @Nil::<T>, |h, t| @Cons(*h, t))
 }
 
@@ -53,7 +53,7 @@ pub fn foldl<T: Copy, U>(z: T, ls: @List<U>, f: fn(&T, &U) -> T) -> T {
  * When function `f` returns true then an option containing the element
  * is returned. If `f` matches no elements then none is returned.
  */
-pub fn find<T: Copy>(ls: @List<T>, f: fn(&T) -> bool) -> Option<T> {
+pub pure fn find<T: Copy>(ls: @List<T>, f: fn(&T) -> bool) -> Option<T> {
     let mut ls = ls;
     loop {
         ls = match *ls {
@@ -88,7 +88,7 @@ pub pure fn is_not_empty<T: Copy>(ls: @List<T>) -> bool {
 }
 
 /// Returns the length of a list
-pub fn len<T>(ls: @List<T>) -> uint {
+pub pure fn len<T>(ls: @List<T>) -> uint {
     let mut count = 0u;
     iter(ls, |_e| count += 1u);
     count
@@ -131,7 +131,7 @@ pure fn push<T: Copy>(ll: &mut @list<T>, vv: T) {
 */
 
 /// Iterate over a list
-pub fn iter<T>(l: @List<T>, f: fn(&T)) {
+pub pure fn iter<T>(l: @List<T>, f: fn(&T)) {
     let mut cur = l;
     loop {
         cur = match *cur {
@@ -145,7 +145,7 @@ pub fn iter<T>(l: @List<T>, f: fn(&T)) {
 }
 
 /// Iterate over a list
-pub fn each<T>(l: @List<T>, f: fn(&T) -> bool) {
+pub pure fn each<T>(l: @List<T>, f: fn(&T) -> bool) {
     let mut cur = l;
     loop {
         cur = match *cur {

src/libstd/rope.rs

@@ -43,7 +43,7 @@ pub type Rope = node::Root;
  */
 
 /// Create an empty rope
-pub fn empty() -> Rope {
+pub pure fn empty() -> Rope {
    return node::Empty;
 }
 
@@ -479,7 +479,7 @@ pub mod iterator {
  *
  * Constant time.
  */
-pub fn height(rope: Rope) -> uint {
+pub pure fn height(rope: Rope) -> uint {
    match (rope) {
       node::Empty      => return 0u,
       node::Content(x) => return node::height(x)
@@ -1019,7 +1019,7 @@ mod node {
                     })
     }
 
-    pub fn height(node: @Node) -> uint {
+    pub pure fn height(node: @Node) -> uint {
         match (*node) {
           Leaf(_)   => return 0u,
           Concat(ref x) => return x.height
@@ -1100,7 +1100,7 @@ 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 {
+    pub pure fn char_at(node: @Node, pos: uint) -> char {
         let mut node    = node;
         let mut pos     = pos;
         loop {