Sync with rust master

Author: alexcrichton

src/lib.rs

@@ -103,7 +103,9 @@
 //! let re = regex!(r"(\d{4})-(\d{2})-(\d{2})");
 //! let text = "2012-03-14, 2013-01-01 and 2014-07-05";
 //! for cap in re.captures_iter(text) {
-//!     println!("Month: {} Day: {} Year: {}", cap.at(2), cap.at(3), cap.at(1));
+//!     println!("Month: {} Day: {} Year: {}",
+//!              cap.at(2).unwrap_or(""), cap.at(3).unwrap_or(""),
+//!              cap.at(1).unwrap_or(""));
 //! }
 //! // Output:
 //! // Month: 03 Day: 14 Year: 2012
@@ -285,7 +287,7 @@
 //! # fn main() {
 //! let re = regex!(r"(?i)a+(?-i)b+");
 //! let cap = re.captures("AaAaAbbBBBb").unwrap();
-//! assert_eq!(cap.at(0), "AaAaAbb");
+//! assert_eq!(cap.at(0), Some("AaAaAbb"));
 //! # }
 //! ```
 //!

src/parse.rs

@@ -838,9 +838,9 @@ impl<'a> Parser<'a> {
     // Otherwise, an error will be returned.
     // Generally, `allow_start` is only true when you're *not* expecting an
     // opening parenthesis.
-    fn pos_last<F>(&self, allow_start: bool, pred: F)
-               -> Result<uint, Error>
-               where F: Fn(&BuildAst) -> bool {
+    fn pos_last<P>(&self, allow_start: bool, pred: P) -> Result<uint, Error> where
+        P: FnMut(&BuildAst) -> bool,
+   {
         let from = match self.stack.iter().rev().position(pred) {
             Some(i) => i,
             None => {
@@ -888,8 +888,9 @@ impl<'a> Parser<'a> {
     // build_from combines all AST elements starting at 'from' in the
     // parser's stack using 'mk' to combine them. If any such element is not an
     // AST then it is popped off the stack and ignored.
-    fn build_from(&mut self, from: uint, mk: |Ast, Ast| -> Ast)
-                 -> Result<Ast, Error> {
+    fn build_from<F>(&mut self, from: uint, mut mk: F) -> Result<Ast, Error> where
+        F: FnMut(Ast, Ast) -> Ast,
+    {
         if from >= self.stack.len() {
             return self.err("Empty group or alternate not allowed.")
         }

src/re.rs

@@ -273,9 +273,9 @@ impl Regex {
     /// let re = regex!(r"'([^']+)'\s+\((\d{4})\)");
     /// let text = "Not my favorite movie: 'Citizen Kane' (1941).";
     /// let caps = re.captures(text).unwrap();
-    /// assert_eq!(caps.at(1), "Citizen Kane");
-    /// assert_eq!(caps.at(2), "1941");
-    /// assert_eq!(caps.at(0), "'Citizen Kane' (1941)");
+    /// assert_eq!(caps.at(1), Some("Citizen Kane"));
+    /// assert_eq!(caps.at(2), Some("1941"));
+    /// assert_eq!(caps.at(0), Some("'Citizen Kane' (1941)"));
     /// # }
     /// ```
     ///
@@ -291,9 +291,9 @@ impl Regex {
     /// let re = regex!(r"'(?P<title>[^']+)'\s+\((?P<year>\d{4})\)");
     /// let text = "Not my favorite movie: 'Citizen Kane' (1941).";
     /// let caps = re.captures(text).unwrap();
-    /// assert_eq!(caps.name("title"), "Citizen Kane");
-    /// assert_eq!(caps.name("year"), "1941");
-    /// assert_eq!(caps.at(0), "'Citizen Kane' (1941)");
+    /// assert_eq!(caps.name("title"), Some("Citizen Kane"));
+    /// assert_eq!(caps.name("year"), Some("1941"));
+    /// assert_eq!(caps.at(0), Some("'Citizen Kane' (1941)"));
     /// # }
     /// ```
     ///
@@ -429,11 +429,12 @@ impl Regex {
     ///
     /// ```rust
     /// # #![feature(phase)]
+    /// # #![feature(unboxed_closures)]
     /// # extern crate regex; #[phase(plugin)] extern crate regex_macros;
     /// # use regex::Captures; fn main() {
     /// let re = regex!(r"([^,\s]+),\s+(\S+)");
-    /// let result = re.replace("Springsteen, Bruce", |caps: &Captures| {
-    ///     format!("{} {}", caps.at(2), caps.at(1))
+    /// let result = re.replace("Springsteen, Bruce", |&: caps: &Captures| {
+    ///     format!("{} {}", caps.at(2).unwrap_or(""), caps.at(1).unwrap_or(""))
     /// });
     /// assert_eq!(result.as_slice(), "Bruce Springsteen");
     /// # }
@@ -585,7 +586,7 @@ impl<'t> Replacer for &'t str {
     }
 }
 
-impl<'t> Replacer for |&Captures|: 't -> String {
+impl<F> Replacer for F where F: FnMut(&Captures) -> String {
     fn reg_replace<'a>(&'a mut self, caps: &Captures) -> CowString<'a> {
         (*self)(caps).into_cow()
     }
@@ -711,27 +712,25 @@ impl<'t> Captures<'t> {
         Some((self.locs[s].unwrap(), self.locs[e].unwrap()))
     }
 
-    /// Returns the matched string for the capture group `i`.
-    /// If `i` isn't a valid capture group or didn't match anything, then the
-    /// empty string is returned.
-    pub fn at(&self, i: uint) -> &'t str {
+    /// Returns the matched string for the capture group `i`.  If `i` isn't
+    /// a valid capture group or didn't match anything, then `None` is
+    /// returned.
+    pub fn at(&self, i: uint) -> Option<&'t str> {
         match self.pos(i) {
-            None => "",
-            Some((s, e)) => {
-                self.text.slice(s, e)
-            }
+            None => None,
+            Some((s, e)) => Some(self.text.slice(s, e))
         }
     }
 
-    /// Returns the matched string for the capture group named `name`.
-    /// If `name` isn't a valid capture group or didn't match anything, then
-    /// the empty string is returned.
-    pub fn name(&self, name: &str) -> &'t str {
+    /// Returns the matched string for the capture group named `name`.  If
+    /// `name` isn't a valid capture group or didn't match anything, then
+    /// `None` is returned.
+    pub fn name(&self, name: &str) -> Option<&'t str> {
         match self.named {
-            None => "",
+            None => None,
             Some(ref h) => {
                 match h.get(name) {
-                    None => "",
+                    None => None,
                     Some(i) => self.at(*i),
                 }
             }
@@ -767,12 +766,13 @@ impl<'t> Captures<'t> {
         // How evil can you get?
         // FIXME: Don't use regexes for this. It's completely unnecessary.
         let re = Regex::new(r"(^|[^$]|\b)\$(\w+)").unwrap();
-        let text = re.replace_all(text, |refs: &Captures| -> String {
-            let (pre, name) = (refs.at(1), refs.at(2));
+        let text = re.replace_all(text, |&mut: refs: &Captures| -> String {
+            let pre = refs.at(1).unwrap_or("");
+            let name = refs.at(2).unwrap_or("");
             format!("{}{}", pre,
                     match from_str::<uint>(name.as_slice()) {
-                None => self.name(name).to_string(),
-                Some(i) => self.at(i).to_string(),
+                None => self.name(name).unwrap_or("").to_string(),
+                Some(i) => self.at(i).unwrap_or("").to_string(),
             })
         });
         let re = Regex::new(r"\$\$").unwrap();
@@ -801,7 +801,7 @@ impl<'t> Iterator<&'t str> for SubCaptures<'t> {
     fn next(&mut self) -> Option<&'t str> {
         if self.idx < self.caps.len() {
             self.idx += 1;
-            Some(self.caps.at(self.idx - 1))
+            Some(self.caps.at(self.idx - 1).unwrap_or(""))
         } else {
             None
         }

src/vm.rs

@@ -38,6 +38,7 @@ pub use self::StepState::*;
 
 use std::cmp;
 use std::mem;
+use std::slice::SliceExt;
 use compile::{
     Program,
     Match, OneChar, CharClass, Any, EmptyBegin, EmptyEnd, EmptyWordBoundary,