std: convert character-based str::find_* to methods. Add .slice_{to,from} methods.

src/compiletest/runtest.rs

@@ -417,7 +417,7 @@ fn scan_until_char(haystack: &str, needle: char, idx: &mut uint) -> bool {
     if *idx >= haystack.len() {
         return false;
     }
-    let opt = str::find_char_from(haystack, needle, *idx);
+    let opt = haystack.slice_from(*idx).find(needle);
     if opt.is_none() {
         return false;
     }

src/libfuzzer/fuzzer.rc

@@ -375,7 +375,7 @@ pub fn check_variants_T<T:Copy>(crate: @ast::crate,
 }
 
 pub fn last_part(filename: ~str) -> ~str {
-    let ix = str::rfind_char(filename, '/').get();
+    let ix = filename.rfind('/').get();
     filename.slice(ix + 1u, filename.len() - 3u).to_owned()
 }
 

src/librustc/middle/lint.rs

@@ -841,26 +841,11 @@ fn check_item_non_camel_case_types(cx: &Context, it: @ast::item) {
     fn is_camel_case(cx: ty::ctxt, ident: ast::ident) -> bool {
         let ident = cx.sess.str_of(ident);
         assert!(!ident.is_empty());
-        let ident = ident_without_trailing_underscores(*ident);
-        let ident = ident_without_leading_underscores(ident);
+        let ident = ident.trim_chars(&['_']);
         char::is_uppercase(str::char_at(ident, 0)) &&
             !ident.contains_char('_')
     }
 
-    fn ident_without_trailing_underscores<'r>(ident: &'r str) -> &'r str {
-        match str::rfind(ident, |c| c != '_') {
-            Some(idx) => ident.slice(0, idx + 1),
-            None => ident, // all underscores
-        }
-    }
-
-    fn ident_without_leading_underscores<'r>(ident: &'r str) -> &'r str {
-        match str::find(ident, |c| c != '_') {
-            Some(idx) => ident.slice(idx, ident.len()),
-            None => ident // all underscores
-        }
-    }
-
     fn check_case(cx: &Context, ident: ast::ident, span: span) {
         if !is_camel_case(cx.tcx, ident) {
             cx.span_lint(non_camel_case_types, span,

src/librustc/middle/resolve.rs

@@ -2681,7 +2681,7 @@ impl Resolver {
         match module_prefix_result {
             Failed => {
                 let mpath = self.idents_to_str(module_path);
-                match str::rfind(self.idents_to_str(module_path), |c| { c == ':' }) {
+                match self.idents_to_str(module_path).rfind(':') {
                     Some(idx) => {
                         self.session.span_err(span, fmt!("unresolved import: could not find `%s` \
                                                          in `%s`", str::substr(mpath, idx,

src/librustdoc/desc_to_brief_pass.rs

@@ -118,19 +118,17 @@ fn first_sentence_(s: &str) -> ~str {
     let mut dotcount = 0;
     // The index of the character following a single dot. This allows
     // Things like [0..1) to appear in the brief description
-    let idx = do str::find(s) |ch| {
+    let idx = s.find(|ch: char| {
         if ch == '.' {
             dotcount += 1;
             false
+        } else if dotcount == 1 {
+            true
         } else {
-            if dotcount == 1 {
-                true
-            } else {
-                dotcount = 0;
-                false
-            }
+            dotcount = 0;
+            false
         }
-    };
+    });
     match idx {
         Some(idx) if idx > 2u => {
             str::to_owned(s.slice(0, idx - 1))

src/librustpkg/version.rs

@@ -175,7 +175,7 @@ pub fn split_version<'a>(s: &'a str) -> Option<(&'a str, Version)> {
     if { let mut i: uint = 0; for str::to_chars(s).each |&c| { if c == '#' { i += 1; } }; i > 1 } {
         return None;
     }
-    match str::rfind_char(s, '#') {
+    match s.rfind('#') {
         Some(i) => {
             debug!("in %s, i = %?", s, i);
             let path = s.slice(0, i);

src/libstd/path.rs

@@ -479,8 +479,8 @@ impl GenericPath for PosixPath {
         match self.filename() {
             None => None,
             Some(ref f) => {
-                match str::rfind_char(*f, '.') {
-                    Some(p) => Some(f.slice(0, p).to_owned()),
+                match f.rfind('.') {
+                    Some(p) => Some(f.slice_to(p).to_owned()),
                     None => Some(copy *f),
                 }
             }
@@ -491,8 +491,8 @@ impl GenericPath for PosixPath {
         match self.filename() {
             None => None,
             Some(ref f) => {
-                match str::rfind_char(*f, '.') {
-                    Some(p) if p < f.len() => Some(f.slice(p, f.len()).to_owned()),
+                match f.rfind('.') {
+                    Some(p) if p < f.len() => Some(f.slice_from(p).to_owned()),
                     _ => None,
                 }
             }
@@ -693,8 +693,8 @@ impl GenericPath for WindowsPath {
         match self.filename() {
             None => None,
             Some(ref f) => {
-                match str::rfind_char(*f, '.') {
-                    Some(p) => Some(f.slice(0, p).to_owned()),
+                match f.rfind('.') {
+                    Some(p) => Some(f.slice_to(p).to_owned()),
                     None => Some(copy *f),
                 }
             }
@@ -705,8 +705,8 @@ impl GenericPath for WindowsPath {
         match self.filename() {
           None => None,
           Some(ref f) => {
-            match str::rfind_char(*f, '.') {
-                Some(p) if p < f.len() => Some(f.slice(p, f.len()).to_owned()),
+            match f.rfind('.') {
+                Some(p) if p < f.len() => Some(f.slice_from(p).to_owned()),
                 _ => None,
             }
           }

src/libstd/str.rs

@@ -21,6 +21,7 @@ use at_vec;
 use cast::transmute;
 use cast;
 use char;
+use char::Char;
 use clone::Clone;
 use cmp::{TotalOrd, Ordering, Less, Equal, Greater};
 use container::Container;
@@ -510,7 +511,7 @@ pub fn unshift_char(s: &mut ~str, ch: char) {
 pub fn trim_left_chars<'a>(s: &'a str, chars_to_trim: &[char]) -> &'a str {
     if chars_to_trim.is_empty() { return s; }
 
-    match find(s, |c| !chars_to_trim.contains(&c)) {
+    match s.find(|c| !chars_to_trim.contains(&c)) {
       None => "",
       Some(first) => unsafe { raw::slice_bytes(s, first, s.len()) }
     }
@@ -528,7 +529,7 @@ pub fn trim_left_chars<'a>(s: &'a str, chars_to_trim: &[char]) -> &'a str {
 pub fn trim_right_chars<'a>(s: &'a str, chars_to_trim: &[char]) -> &'a str {
     if chars_to_trim.is_empty() { return s; }
 
-    match rfind(s, |c| !chars_to_trim.contains(&c)) {
+    match s.rfind(|c| !chars_to_trim.contains(&c)) {
       None => "",
       Some(last) => {
         let next = char_range_at(s, last).next;
@@ -552,7 +553,7 @@ pub fn trim_chars<'a>(s: &'a str, chars_to_trim: &[char]) -> &'a str {
 
 /// Returns a string with leading whitespace removed
 pub fn trim_left<'a>(s: &'a str) -> &'a str {
-    match find(s, |c| !char::is_whitespace(c)) {
+    match s.find(|c| !char::is_whitespace(c)) {
       None => "",
       Some(first) => unsafe { raw::slice_bytes(s, first, s.len()) }
     }
@@ -560,7 +561,7 @@ pub fn trim_left<'a>(s: &'a str) -> &'a str {
 
 /// Returns a string with trailing whitespace removed
 pub fn trim_right<'a>(s: &'a str) -> &'a str {
-    match rfind(s, |c| !char::is_whitespace(c)) {
+    match s.rfind(|c| !char::is_whitespace(c)) {
       None => "",
       Some(last) => {
         let next = char_range_at(s, last).next;
@@ -621,6 +622,34 @@ pub fn substr<'a>(s: &'a str, begin: uint, n: uint) -> &'a str {
     s.slice(begin, begin + count_bytes(s, begin, n))
 }
 
+/// Something that can be used to compare against a character
+pub trait CharEq {
+    /// Determine if the splitter should split at the given character
+    fn matches(&self, char) -> bool;
+    /// Indicate if this is only concerned about ASCII characters,
+    /// which can allow for a faster implementation.
+    fn only_ascii(&self) -> bool;
+}
+impl CharEq for char {
+    #[inline(always)]
+    fn matches(&self, c: char) -> bool { *self == c }
+
+    fn only_ascii(&self) -> bool { (*self as uint) < 128 }
+}
+impl<'self> CharEq for &'self fn(char) -> bool {
+    #[inline(always)]
+    fn matches(&self, c: char) -> bool { (*self)(c) }
+
+    fn only_ascii(&self) -> bool { false }
+}
+impl CharEq for extern "Rust" fn(char) -> bool {
+    #[inline(always)]
+    fn matches(&self, c: char) -> bool { (*self)(c) }
+
+    fn only_ascii(&self) -> bool { false }
+}
+
+
 /// An iterator over the substrings of a string, separated by `sep`.
 pub struct StrCharSplitIterator<'self,Sep> {
     priv string: &'self str,
@@ -639,34 +668,7 @@ pub type WordIterator<'self> =
     FilterIterator<'self, &'self str,
              StrCharSplitIterator<'self, extern "Rust" fn(char) -> bool>>;
 
-/// A separator for splitting a string character-wise
-pub trait StrCharSplitSeparator {
-    /// Determine if the splitter should split at the given character
-    fn should_split(&self, char) -> bool;
-    /// Indicate if the splitter only uses ASCII characters, which
-    /// allows for a faster implementation.
-    fn only_ascii(&self) -> bool;
-}
-impl StrCharSplitSeparator for char {
-    #[inline(always)]
-    fn should_split(&self, c: char) -> bool { *self == c }
-
-    fn only_ascii(&self) -> bool { (*self as uint) < 128 }
-}
-impl<'self> StrCharSplitSeparator for &'self fn(char) -> bool {
-    #[inline(always)]
-    fn should_split(&self, c: char) -> bool { (*self)(c) }
-
-    fn only_ascii(&self) -> bool { false }
-}
-impl<'self> StrCharSplitSeparator for extern "Rust" fn(char) -> bool {
-    #[inline(always)]
-    fn should_split(&self, c: char) -> bool { (*self)(c) }
-
-    fn only_ascii(&self) -> bool { false }
-}
-
-impl<'self, Sep: StrCharSplitSeparator> Iterator<&'self str> for StrCharSplitIterator<'self, Sep> {
+impl<'self, Sep: CharEq> Iterator<&'self str> for StrCharSplitIterator<'self, Sep> {
     #[inline]
     fn next(&mut self) -> Option<&'self str> {
         if self.finished { return None }
@@ -680,7 +682,7 @@ impl<'self, Sep: StrCharSplitSeparator> Iterator<&'self str> for StrCharSplitIte
             while self.position < l && self.count > 0 {
                 let byte = self.string[self.position];
 
-                if self.sep.should_split(byte as char) {
+                if self.sep.matches(byte as char) {
                     let slice = unsafe { raw::slice_bytes(self.string, start, self.position) };
                     self.position += 1;
                     self.count -= 1;
@@ -692,7 +694,7 @@ impl<'self, Sep: StrCharSplitSeparator> Iterator<&'self str> for StrCharSplitIte
             while self.position < l && self.count > 0 {
                 let CharRange {ch, next} = char_range_at(self.string, self.position);
 
-                if self.sep.should_split(ch) {
+                if self.sep.matches(ch) {
                     let slice = unsafe { raw::slice_bytes(self.string, start, self.position) };
                     self.position = next;
                     self.count -= 1;
@@ -1157,318 +1159,6 @@ pub fn map(ss: &str, ff: &fn(char) -> char) -> ~str {
 Section: Searching
 */
 
-/**
- * Returns the byte index of the first matching character
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `c` - The character to search for
- *
- * # Return value
- *
- * An `option` containing the byte index of the first matching character
- * or `none` if there is no match
- */
-pub fn find_char(s: &str, c: char) -> Option<uint> {
-    find_char_between(s, c, 0u, s.len())
-}
-
-/**
- * Returns the byte index of the first matching character beginning
- * from a given byte offset
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `c` - The character to search for
- * * `start` - The byte index to begin searching at, inclusive
- *
- * # Return value
- *
- * An `option` containing the byte index of the first matching character
- * or `none` if there is no match
- *
- * # Failure
- *
- * `start` must be less than or equal to `s.len()`. `start` must be the
- * index of a character boundary, as defined by `is_char_boundary`.
- */
-pub fn find_char_from(s: &str, c: char, start: uint) -> Option<uint> {
-    find_char_between(s, c, start, s.len())
-}
-
-/**
- * Returns the byte index of the first matching character within a given range
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `c` - The character to search for
- * * `start` - The byte index to begin searching at, inclusive
- * * `end` - The byte index to end searching at, exclusive
- *
- * # Return value
- *
- * An `option` containing the byte index of the first matching character
- * or `none` if there is no match
- *
- * # Failure
- *
- * `start` must be less than or equal to `end` and `end` must be less than
- * or equal to `s.len()`. `start` must be the index of a character boundary,
- * as defined by `is_char_boundary`.
- */
-pub fn find_char_between(s: &str, c: char, start: uint, end: uint)
-    -> Option<uint> {
-    if c < 128u as char {
-        assert!(start <= end);
-        assert!(end <= s.len());
-        let mut i = start;
-        let b = c as u8;
-        while i < end {
-            if s[i] == b { return Some(i); }
-            i += 1u;
-        }
-        return None;
-    } else {
-        find_between(s, start, end, |x| x == c)
-    }
-}
-
-/**
- * Returns the byte index of the last matching character
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `c` - The character to search for
- *
- * # Return value
- *
- * An `option` containing the byte index of the last matching character
- * or `none` if there is no match
- */
-pub fn rfind_char(s: &str, c: char) -> Option<uint> {
-    rfind_char_between(s, c, s.len(), 0u)
-}
-
-/**
- * Returns the byte index of the last matching character beginning
- * from a given byte offset
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `c` - The character to search for
- * * `start` - The byte index to begin searching at, exclusive
- *
- * # Return value
- *
- * An `option` containing the byte index of the last matching character
- * or `none` if there is no match
- *
- * # Failure
- *
- * `start` must be less than or equal to `s.len()`. `start` must be
- * the index of a character boundary, as defined by `is_char_boundary`.
- */
-pub fn rfind_char_from(s: &str, c: char, start: uint) -> Option<uint> {
-    rfind_char_between(s, c, start, 0u)
-}
-
-/**
- * Returns the byte index of the last matching character within a given range
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `c` - The character to search for
- * * `start` - The byte index to begin searching at, exclusive
- * * `end` - The byte index to end searching at, inclusive
- *
- * # Return value
- *
- * An `option` containing the byte index of the last matching character
- * or `none` if there is no match
- *
- * # Failure
- *
- * `end` must be less than or equal to `start` and `start` must be less than
- * or equal to `s.len()`. `start` must be the index of a character boundary,
- * as defined by `is_char_boundary`.
- */
-pub fn rfind_char_between(s: &str, c: char, start: uint, end: uint) -> Option<uint> {
-    if c < 128u as char {
-        assert!(start >= end);
-        assert!(start <= s.len());
-        let mut i = start;
-        let b = c as u8;
-        while i > end {
-            i -= 1u;
-            if s[i] == b { return Some(i); }
-        }
-        return None;
-    } else {
-        rfind_between(s, start, end, |x| x == c)
-    }
-}
-
-/**
- * Returns the byte index of the first character that satisfies
- * the given predicate
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `f` - The predicate to satisfy
- *
- * # Return value
- *
- * An `option` containing the byte index of the first matching character
- * or `none` if there is no match
- */
-pub fn find(s: &str, f: &fn(char) -> bool) -> Option<uint> {
-    find_between(s, 0u, s.len(), f)
-}
-
-/**
- * Returns the byte index of the first character that satisfies
- * the given predicate, beginning from a given byte offset
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `start` - The byte index to begin searching at, inclusive
- * * `f` - The predicate to satisfy
- *
- * # Return value
- *
- * An `option` containing the byte index of the first matching charactor
- * or `none` if there is no match
- *
- * # Failure
- *
- * `start` must be less than or equal to `s.len()`. `start` must be the
- * index of a character boundary, as defined by `is_char_boundary`.
- */
-pub fn find_from(s: &str, start: uint, f: &fn(char)
-    -> bool) -> Option<uint> {
-    find_between(s, start, s.len(), f)
-}
-
-/**
- * Returns the byte index of the first character that satisfies
- * the given predicate, within a given range
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `start` - The byte index to begin searching at, inclusive
- * * `end` - The byte index to end searching at, exclusive
- * * `f` - The predicate to satisfy
- *
- * # Return value
- *
- * An `option` containing the byte index of the first matching character
- * or `none` if there is no match
- *
- * # Failure
- *
- * `start` must be less than or equal to `end` and `end` must be less than
- * or equal to `s.len()`. `start` must be the index of a character
- * boundary, as defined by `is_char_boundary`.
- */
-pub fn find_between(s: &str, start: uint, end: uint, f: &fn(char) -> bool) -> Option<uint> {
-    assert!(start <= end);
-    assert!(end <= s.len());
-    assert!(is_char_boundary(s, start));
-    let mut i = start;
-    while i < end {
-        let CharRange {ch, next} = char_range_at(s, i);
-        if f(ch) { return Some(i); }
-        i = next;
-    }
-    return None;
-}
-
-/**
- * Returns the byte index of the last character that satisfies
- * the given predicate
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `f` - The predicate to satisfy
- *
- * # Return value
- *
- * An option containing the byte index of the last matching character
- * or `none` if there is no match
- */
-pub fn rfind(s: &str, f: &fn(char) -> bool) -> Option<uint> {
-    rfind_between(s, s.len(), 0u, f)
-}
-
-/**
- * Returns the byte index of the last character that satisfies
- * the given predicate, beginning from a given byte offset
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `start` - The byte index to begin searching at, exclusive
- * * `f` - The predicate to satisfy
- *
- * # Return value
- *
- * An `option` containing the byte index of the last matching character
- * or `none` if there is no match
- *
- * # Failure
- *
- * `start` must be less than or equal to `s.len()', `start` must be the
- * index of a character boundary, as defined by `is_char_boundary`
- */
-pub fn rfind_from(s: &str, start: uint, f: &fn(char) -> bool) -> Option<uint> {
-    rfind_between(s, start, 0u, f)
-}
-
-/**
- * Returns the byte index of the last character that satisfies
- * the given predicate, within a given range
- *
- * # Arguments
- *
- * * `s` - The string to search
- * * `start` - The byte index to begin searching at, exclusive
- * * `end` - The byte index to end searching at, inclusive
- * * `f` - The predicate to satisfy
- *
- * # Return value
- *
- * An `option` containing the byte index of the last matching character
- * or `none` if there is no match
- *
- * # Failure
- *
- * `end` must be less than or equal to `start` and `start` must be less
- * than or equal to `s.len()`. `start` must be the index of a character
- * boundary, as defined by `is_char_boundary`
- */
-pub fn rfind_between(s: &str, start: uint, end: uint, f: &fn(char) -> bool) -> Option<uint> {
-    assert!(start >= end);
-    assert!(start <= s.len());
-    assert!(is_char_boundary(s, start));
-    let mut i = start;
-    while i > end {
-        let CharRange {ch, next: prev} = char_range_at_reverse(s, i);
-        if f(ch) { return Some(prev); }
-        i = prev;
-    }
-    return None;
-}
-
 // Utility used by various searching functions
 fn match_at<'a,'b>(haystack: &'a str, needle: &'b str, at: uint) -> bool {
     let mut i = at;
@@ -1580,7 +1270,7 @@ pub fn contains<'a,'b>(haystack: &'a str, needle: &'b str) -> bool {
  * * needle - The char to look for
  */
 pub fn contains_char(haystack: &str, needle: char) -> bool {
-    find_char(haystack, needle).is_some()
+    haystack.find(needle).is_some()
 }
 
 /**
@@ -2415,11 +2105,9 @@ pub trait StrSlice<'self> {
     fn rev_iter(&self) -> StrCharRevIterator<'self>;
     fn bytes_iter(&self) -> StrBytesIterator<'self>;
     fn bytes_rev_iter(&self) -> StrBytesRevIterator<'self>;
-    fn split_iter<Sep: StrCharSplitSeparator>(&self, sep: Sep) -> StrCharSplitIterator<'self, Sep>;
-    fn splitn_iter<Sep: StrCharSplitSeparator>(&self, sep: Sep, count: uint)
-        -> StrCharSplitIterator<'self, Sep>;
-    fn split_options_iter<Sep: StrCharSplitSeparator>(&self, sep: Sep,
-                                                      count: uint, allow_trailing_empty: bool)
+    fn split_iter<Sep: CharEq>(&self, sep: Sep) -> StrCharSplitIterator<'self, Sep>;
+    fn splitn_iter<Sep: CharEq>(&self, sep: Sep, count: uint) -> StrCharSplitIterator<'self, Sep>;
+    fn split_options_iter<Sep: CharEq>(&self, sep: Sep, count: uint, allow_trailing_empty: bool)
         -> StrCharSplitIterator<'self, Sep>;
     /// An iterator over the start and end indices of each match of
     /// `sep` within `self`.
@@ -2448,6 +2136,8 @@ pub trait StrSlice<'self> {
     fn len(&self) -> uint;
     fn char_len(&self) -> uint;
     fn slice(&self, begin: uint, end: uint) -> &'self str;
+    fn slice_from(&self, begin: uint) -> &'self str;
+    fn slice_to(&self, end: uint) -> &'self str;
     fn starts_with<'a>(&self, needle: &'a str) -> bool;
     fn substr(&self, begin: uint, n: uint) -> &'self str;
     fn escape_default(&self) -> ~str;
@@ -2463,6 +2153,9 @@ pub trait StrSlice<'self> {
     fn char_at(&self, i: uint) -> char;
     fn char_at_reverse(&self, i: uint) -> char;
     fn to_bytes(&self) -> ~[u8];
+
+    fn find<C: CharEq>(&self, search: C) -> Option<uint>;
+    fn rfind<C: CharEq>(&self, search: C) -> Option<uint>;
 }
 
 /// Extension methods for strings
@@ -2500,16 +2193,14 @@ impl<'self> StrSlice<'self> for &'self str {
         StrBytesRevIterator { it: as_bytes_slice(*self).rev_iter() }
     }
 
-    fn split_iter<Sep: StrCharSplitSeparator>(&self, sep: Sep) -> StrCharSplitIterator<'self, Sep> {
+    fn split_iter<Sep: CharEq>(&self, sep: Sep) -> StrCharSplitIterator<'self, Sep> {
         self.split_options_iter(sep, self.len(), true)
     }
 
-    fn splitn_iter<Sep: StrCharSplitSeparator>(&self, sep: Sep, count: uint)
-        -> StrCharSplitIterator<'self, Sep> {
+    fn splitn_iter<Sep: CharEq>(&self, sep: Sep, count: uint) -> StrCharSplitIterator<'self, Sep> {
         self.split_options_iter(sep, count, true)
     }
-    fn split_options_iter<Sep: StrCharSplitSeparator>(&self, sep: Sep,
-                                                      count: uint, allow_trailing_empty: bool)
+    fn split_options_iter<Sep: CharEq>(&self, sep: Sep, count: uint, allow_trailing_empty: bool)
         -> StrCharSplitIterator<'self, Sep> {
         let only_ascii = sep.only_ascii();
         StrCharSplitIterator {
@@ -2590,6 +2281,14 @@ impl<'self> StrSlice<'self> for &'self str {
         unsafe { raw::slice_bytes(*self, begin, end) }
     }
     #[inline]
+    fn slice_from(&self, begin: uint) -> &'self str {
+        self.slice(begin, self.len())
+    }
+    #[inline]
+    fn slice_to(&self, end: uint) -> &'self str {
+        self.slice(0, end)
+    }
+    #[inline]
     fn starts_with<'a>(&self, needle: &'a str) -> bool {
         starts_with(*self, needle)
     }
@@ -2654,6 +2353,54 @@ impl<'self> StrSlice<'self> for &'self str {
     }
 
     fn to_bytes(&self) -> ~[u8] { to_bytes(*self) }
+
+    /**
+     * Returns the byte index of the first character of `self` that matches `search`
+     *
+     * # Return value
+     *
+     * `Some` containing the byte index of the last matching character
+     * or `None` if there is no match
+     */
+    fn find<C: CharEq>(&self, search: C) -> Option<uint> {
+        if search.only_ascii() {
+            for self.bytes_iter().enumerate().advance |(i, b)| {
+                if search.matches(b as char) { return Some(i) }
+            }
+        } else {
+            let mut index = 0;
+            for self.iter().advance |c| {
+                if search.matches(c) { return Some(index); }
+                index += c.len_utf8_bytes();
+            }
+        }
+
+        None
+    }
+    /**
+     * Returns the byte index of the last character of `self` that matches `search`
+     *
+     * # Return value
+     *
+     * `Some` containing the byte index of the last matching character
+     * or `None` if there is no match
+     */
+    fn rfind<C: CharEq>(&self, search: C) -> Option<uint> {
+        let mut index = self.len();
+        if search.only_ascii() {
+            for self.bytes_rev_iter().advance |b| {
+                index -= 1;
+                if search.matches(b as char) { return Some(index); }
+            }
+        } else {
+            for self.rev_iter().advance |c| {
+                index -= c.len_utf8_bytes();
+                if search.matches(c) { return Some(index); }
+            }
+        }
+
+        None
+    }
 }
 
 #[allow(missing_doc)]
@@ -2803,12 +2550,23 @@ mod tests {
     }
 
     #[test]
-    fn test_rfind_char() {
-        assert_eq!(rfind_char("hello", 'l'), Some(3u));
-        assert_eq!(rfind_char("hello", 'o'), Some(4u));
-        assert_eq!(rfind_char("hello", 'h'), Some(0u));
-        assert!(rfind_char("hello", 'z').is_none());
-        assert_eq!(rfind_char("ประเทศไทย中华Việt Nam", '华'), Some(30u));
+    fn test_find() {
+        assert_eq!("hello".find('l'), Some(2u));
+        assert_eq!("hello".find(|c:char| c == 'o'), Some(4u));
+        assert!("hello".find('x').is_none());
+        assert!("hello".find(|c:char| c == 'x').is_none());
+        assert_eq!("ประเทศไทย中华Việt Nam".find('华'), Some(30u));
+        assert_eq!("ประเทศไทย中华Việt Nam".find(|c: char| c == '华'), Some(30u));
+    }
+
+    #[test]
+    fn test_rfind() {
+        assert_eq!("hello".rfind('l'), Some(3u));
+        assert_eq!("hello".rfind(|c:char| c == 'o'), Some(4u));
+        assert!("hello".rfind('x').is_none());
+        assert!("hello".rfind(|c:char| c == 'x').is_none());
+        assert_eq!("ประเทศไทย中华Việt Nam".rfind('华'), Some(30u));
+        assert_eq!("ประเทศไทย中华Việt Nam".rfind(|c: char| c == '华'), Some(30u));
     }
 
     #[test]
@@ -3122,6 +2880,19 @@ mod tests {
         "中华Việt Nam".slice(0u, 2u);
     }
 
+    #[test]
+    fn test_slice_from() {
+        assert_eq!("abcd".slice_from(0), "abcd");
+        assert_eq!("abcd".slice_from(2), "cd");
+        assert_eq!("abcd".slice_from(4), "");
+    }
+    #[test]
+    fn test_slice_to() {
+        assert_eq!("abcd".slice_to(0), "");
+        assert_eq!("abcd".slice_to(2), "ab");
+        assert_eq!("abcd".slice_to(4), "abcd");
+    }
+
     #[test]
     fn test_trim_left_chars() {
         assert!(trim_left_chars(" *** foo *** ", []) == " *** foo *** ");

src/libsyntax/codemap.rs

@@ -24,7 +24,6 @@ source code snippets, etc.
 use core::prelude::*;
 
 use core::cmp;
-use core::str;
 use core::to_bytes;
 use core::uint;
 use extra::serialize::{Encodable, Decodable, Encoder, Decoder};
@@ -288,11 +287,11 @@ impl FileMap {
     pub fn get_line(&self, line: int) -> ~str {
         let begin: BytePos = self.lines[line] - self.start_pos;
         let begin = begin.to_uint();
-        let end = match str::find_char_from(*self.src, '\n', begin) {
-            Some(e) => e,
-            None => self.src.len()
-        };
-        self.src.slice(begin, end).to_owned()
+        let slice = self.src.slice_from(begin);
+        match slice.find('\n') {
+            Some(e) => slice.slice_to(e).to_owned(),
+            None => slice.to_owned()
+        }
     }
 
     pub fn record_multibyte_char(&self, pos: BytePos, bytes: uint) {