---

yaml
---
r: 125947
b: refs/heads/try
c: 1cfa656
h: refs/heads/master
i:
  125945: 5558ccb
  125943: af607ec
v: v3

Author: nham

[refs]

@@ -2,7 +2,7 @@
 refs/heads/master: f2fa55903e378368ed9173560f03a0ef16e371c2
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: 9fc8394d3bce22ab483f98842434c84c396212ae
-refs/heads/try: 769dae0a00f04bae5ffba6c9f3c0cf2478782be1
+refs/heads/try: 1cfa6569f9078090ac317af432adf712407bd4f7
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
 refs/heads/try2: 147ecfdd8221e4a4d4e090486829a06da1e0ca3c

branches/try/src/etc/licenseck.py

@@ -44,7 +44,6 @@
     "libsync/mpsc_intrusive.rs", # BSD
     "test/bench/shootout-binarytrees.rs", # BSD
     "test/bench/shootout-fannkuch-redux.rs", # BSD
-    "test/bench/shootout-k-nucleotide.rs", # BSD
     "test/bench/shootout-mandelbrot.rs", # BSD
     "test/bench/shootout-meteor.rs", # BSD
     "test/bench/shootout-pidigits.rs", # BSD

branches/try/src/grammar/raw-string-literal-ambiguity.md

@@ -1,11 +1,7 @@
 Rust's lexical grammar is not context-free. Raw string literals are the source
 of the problem. Informally, a raw string literal is an `r`, followed by `N`
 hashes (where N can be zero), a quote, any characters, then a quote followed
-by `N` hashes. Critically, once inside the first pair of quotes,
-another quote cannot be followed by `N` consecutive hashes. e.g.
-`r###""###"###` is invalid.
-
-This grammar describes this as best possible:
+by `N` hashes. This grammar describes this as best possible:
 
     R -> 'r' S
     S -> '"' B '"'
@@ -26,39 +22,8 @@ accepted as one by the above grammar, using the derivation:
 (Where `T : U` means the rule `T` is applied, and `U` is the remainder of the
 string.) The difficulty arises from the fact that it is fundamentally
 context-sensitive. In particular, the context needed is the number of hashes.
-
-To prove that Rust's string literals are not context-free, we will use
-the fact that context-free languages are closed under intersection with
-regular languages, and the
-[pumping lemma for context-free languages](https://en.wikipedia.org/wiki/Pumping_lemma_for_context-free_languages).
-
-Consider the regular language `R = r#+""#*"#+`. If Rust's raw string literals are
-context-free, then their intersection with `R`, `R'`, should also be context-free.
-Therefore, to prove that raw string literals are not context-free,
-it is sufficient to prove that `R'` is not context-free.
-
-The language `R'` is `{r#^n""#^m"#^n | m < n}`.
-
-Assume `R'` *is* context-free. Then `R'` has some pumping length `p > 0` for which
-the pumping lemma applies. Consider the following string `s` in `R'`:
-
-`r#^p""#^{p-1}"#^p`
-
-e.g. for `p = 2`: `s = r##""#"##`
-
-Then `s = uvwxy` for some choice of `uvwxy` such that `vx` is non-empty,
-`|vwx| < p+1`, and `uv^iwx^iy` is in `R'` for all `i >= 0`.
-
-Neither `v` nor `x` can contain a `"` or `r`, as the number of these characters
-in any string in `R'` is fixed. So `v` and `x` contain only hashes.
-Consequently, of the three sequences of hashes, `v` and `x` combined
-can only pump two of them.
-If we ever choose the central sequence of hashes, then one of the outer sequences
-will not grow when we pump, leading to an imbalance between the outer sequences.
-Therefore, we must pump both outer sequences of hashes. However,
-there are `p+2` characters between these two sequences of hashes, and `|vwx|` must
-be less than `p+1`. Therefore we have a contradiction, and `R'` must not be
-context-free.
-
-Since `R'` is not context-free, it follows that the Rust's raw string literals
-must not be context-free.
+I know of no way to resolve this, but also have not come up with a proof that
+it is not context sensitive. Such a proof would probably use the pumping lemma
+for context-free languages, but I (cmr) could not come up with a proof after
+spending a few hours on it, and decided my time best spent elsewhere. Pull
+request welcome!

branches/try/src/libcollections/ringbuf.rs

@@ -19,6 +19,7 @@ use core::cmp;
 use core::default::Default;
 use core::fmt;
 use core::iter::RandomAccessIterator;
+use std::hash::{Writer, Hash};
 
 use {Deque, Collection, Mutable, MutableSeq};
 use vec::Vec;
@@ -450,6 +451,14 @@ impl<A: PartialEq> PartialEq for RingBuf<A> {
     }
 }
 
+impl<S: Writer, A: Hash<S>> Hash<S> for RingBuf<A> {
+    fn hash(&self, state: &mut S) {
+        for elt in self.iter() {
+            elt.hash(state);
+        }
+    }
+}
+
 impl<A> FromIterator<A> for RingBuf<A> {
     fn from_iter<T: Iterator<A>>(iterator: T) -> RingBuf<A> {
         let (lower, _) = iterator.size_hint();
@@ -485,6 +494,7 @@ mod tests {
     use std::fmt::Show;
     use std::prelude::*;
     use std::gc::{GC, Gc};
+    use std::hash;
     use test::Bencher;
     use test;
 
@@ -912,6 +922,24 @@ mod tests {
         assert!(e == RingBuf::new());
     }
 
+    #[test]
+    fn test_hash() {
+      let mut x = RingBuf::new();
+      let mut y = RingBuf::new();
+
+      x.push(1i);
+      x.push(2);
+      x.push(3);
+
+      y.push(0i);
+      y.push(1i);
+      y.pop_front();
+      y.push(2);
+      y.push(3);
+
+      assert!(hash::hash(&x) == hash::hash(&y));
+    }
+
     #[test]
     fn test_show() {
         let ringbuf: RingBuf<int> = range(0i, 10).collect();

branches/try/src/libcollections/smallintmap.rs

@@ -24,8 +24,6 @@ use core::mem::replace;
 use {Collection, Mutable, Map, MutableMap, MutableSeq};
 use {vec, slice};
 use vec::Vec;
-use hash;
-use hash::Hash;
 
 /// A map optimized for small integer keys.
 ///
@@ -60,7 +58,6 @@ use hash::Hash;
 /// months.clear();
 /// assert!(months.is_empty());
 /// ```
-#[deriving(PartialEq, Eq)]
 pub struct SmallIntMap<T> {
     v: Vec<Option<T>>,
 }
@@ -154,27 +151,6 @@ impl<V> Default for SmallIntMap<V> {
     fn default() -> SmallIntMap<V> { SmallIntMap::new() }
 }
 
-impl<V:Clone> Clone for SmallIntMap<V> {
-    #[inline]
-    fn clone(&self) -> SmallIntMap<V> {
-        SmallIntMap { v: self.v.clone() }
-    }
-
-    #[inline]
-    fn clone_from(&mut self, source: &SmallIntMap<V>) {
-        self.v.reserve(source.v.len());
-        for (i, w) in self.v.mut_iter().enumerate() {
-            *w = source.v[i].clone();
-        }
-    }
-}
-
-impl <S: hash::Writer, T: Hash<S>> Hash<S> for SmallIntMap<T> {
-    fn hash(&self, state: &mut S) {
-        self.v.hash(state)
-    }
-}
-
 impl<V> SmallIntMap<V> {
     /// Create an empty SmallIntMap.
     ///
@@ -386,22 +362,6 @@ impl<V: fmt::Show> fmt::Show for SmallIntMap<V> {
     }
 }
 
-impl<V> FromIterator<(uint, V)> for SmallIntMap<V> {
-    fn from_iter<Iter: Iterator<(uint, V)>>(iter: Iter) -> SmallIntMap<V> {
-        let mut map = SmallIntMap::new();
-        map.extend(iter);
-        map
-    }
-}
-
-impl<V> Extendable<(uint, V)> for SmallIntMap<V> {
-    fn extend<Iter: Iterator<(uint, V)>>(&mut self, mut iter: Iter) {
-        for (k, v) in iter {
-            self.insert(k, v);
-        }
-    }
-}
-
 macro_rules! iterator {
     (impl $name:ident -> $elem:ty, $getter:ident) => {
         impl<'a, T> Iterator<$elem> for $name<'a, T> {
@@ -486,10 +446,8 @@ pub type Values<'a, T> =
 #[cfg(test)]
 mod test_map {
     use std::prelude::*;
-    use vec::Vec;
-    use hash;
 
-    use {Map, MutableMap, Mutable, MutableSeq};
+    use {Map, MutableMap, Mutable};
     use super::SmallIntMap;
 
     #[test]
@@ -740,63 +698,6 @@ mod test_map {
         assert!(map_str == "{1: 2, 3: 4}" || map_str == "{3: 4, 1: 2}");
         assert_eq!(format!("{}", empty), "{}".to_string());
     }
-
-    #[test]
-    fn test_clone() {
-        let mut a = SmallIntMap::new();
-
-        a.insert(1, 'x');
-        a.insert(4, 'y');
-        a.insert(6, 'z');
-
-        assert!(a.clone() == a);
-    }
-
-    #[test]
-    fn test_eq() {
-        let mut a = SmallIntMap::new();
-        let mut b = SmallIntMap::new();
-
-        assert!(a == b);
-        assert!(a.insert(0, 5i));
-        assert!(a != b);
-        assert!(b.insert(0, 4i));
-        assert!(a != b);
-        assert!(a.insert(5, 19));
-        assert!(a != b);
-        assert!(!b.insert(0, 5));
-        assert!(a != b);
-        assert!(b.insert(5, 19));
-        assert!(a == b);
-    }
-
-    #[test]
-    fn test_hash() {
-        let mut x = SmallIntMap::new();
-        let mut y = SmallIntMap::new();
-
-        assert!(hash::hash(&x) == hash::hash(&y));
-        x.insert(1, 'a');
-        x.insert(2, 'b');
-        x.insert(3, 'c');
-
-        y.insert(3, 'c');
-        y.insert(2, 'b');
-        y.insert(1, 'a');
-
-        assert!(hash::hash(&x) == hash::hash(&y));
-    }
-
-    #[test]
-    fn test_from_iter() {
-        let xs: Vec<(uint, char)> = vec![(1u, 'a'), (2, 'b'), (3, 'c'), (4, 'd'), (5, 'e')];
-
-        let map: SmallIntMap<char> = xs.iter().map(|&x| x).collect();
-
-        for &(k, v) in xs.iter() {
-            assert_eq!(map.find(&k), Some(&v));
-        }
-    }
 }
 
 #[cfg(test)]