auto merge of #19741 : alexcrichton/rust/stabilize-str, r=aturon

This commit starts out by consolidating all `str` extension traits into one
`StrExt` trait to be included in the prelude. This means that
`UnicodeStrPrelude`, `StrPrelude`, and `StrAllocating` have all been merged into
one `StrExt` exported by the standard library. Some functionality is currently
duplicated with the `StrExt` present in libcore.

This commit also currently avoids any methods which require any form of pattern
to operate. These functions will be stabilized via a separate RFC.

Next, stability of methods and structures are as follows:

Stable

* from_utf8_unchecked
* CowString - after moving to std::string
* StrExt::as_bytes
* StrExt::as_ptr
* StrExt::bytes/Bytes - also made a struct instead of a typedef
* StrExt::char_indices/CharIndices - CharOffsets was renamed
* StrExt::chars/Chars
* StrExt::is_empty
* StrExt::len
* StrExt::lines/Lines
* StrExt::lines_any/LinesAny
* StrExt::slice_unchecked
* StrExt::trim
* StrExt::trim_left
* StrExt::trim_right
* StrExt::words/Words - also made a struct instead of a typedef

Unstable

* from_utf8 - the error type was changed to a `Result`, but the error type has
              yet to prove itself
* from_c_str - this function will be handled by the c_str RFC
* FromStr - this trait will have an associated error type eventually
* StrExt::escape_default - needs iterators at least, unsure if it should make
                           the cut
* StrExt::escape_unicode - needs iterators at least, unsure if it should make
                           the cut
* StrExt::slice_chars - this function has yet to prove itself
* StrExt::slice_shift_char - awaiting conventions about slicing and shifting
* StrExt::graphemes/Graphemes - this functionality may only be in libunicode
* StrExt::grapheme_indices/GraphemeIndices - this functionality may only be in
                                             libunicode
* StrExt::width - this functionality may only be in libunicode
* StrExt::utf16_units - this functionality may only be in libunicode
* StrExt::nfd_chars - this functionality may only be in libunicode
* StrExt::nfkd_chars - this functionality may only be in libunicode
* StrExt::nfc_chars - this functionality may only be in libunicode
* StrExt::nfkc_chars - this functionality may only be in libunicode
* StrExt::is_char_boundary - naming is uncertain with container conventions
* StrExt::char_range_at - naming is uncertain with container conventions
* StrExt::char_range_at_reverse - naming is uncertain with container conventions
* StrExt::char_at - naming is uncertain with container conventions
* StrExt::char_at_reverse - naming is uncertain with container conventions
* StrVector::concat - this functionality may be replaced with iterators, but
                      it's not certain at this time
* StrVector::connect - as with concat, may be deprecated in favor of iterators

Deprecated

* StrAllocating and UnicodeStrPrelude have been merged into StrExit
* eq_slice - compiler implementation detail
* from_str - use the inherent parse() method
* is_utf8 - call from_utf8 instead
* replace - call the method instead
* truncate_utf16_at_nul - this is an implementation detail of windows and does
                          not need to be exposed.
* utf8_char_width - moved to libunicode
* utf16_items - moved to libunicode
* is_utf16 - moved to libunicode
* Utf16Items - moved to libunicode
* Utf16Item - moved to libunicode
* Utf16Encoder - moved to libunicode
* AnyLines - renamed to LinesAny and made a struct
* SendStr - use CowString<'static> instead
* str::raw - all functionality is deprecated
* StrExt::into_string - call to_string() instead
* StrExt::repeat - use iterators instead
* StrExt::char_len - use .chars().count() instead
* StrExt::is_alphanumeric - use .chars().all(..)
* StrExt::is_whitespace - use .chars().all(..)

Pending deprecation -- while slicing syntax is being worked out, these methods
are all #[unstable]

* Str - while currently used for generic programming, this trait will be
        replaced with one of [], deref coercions, or a generic conversion trait.
* StrExt::slice - use slicing syntax instead
* StrExt::slice_to - use slicing syntax instead
* StrExt::slice_from - use slicing syntax instead
* StrExt::lev_distance - deprecated with no replacement

Awaiting stabilization due to patterns and/or matching

* StrExt::contains
* StrExt::contains_char
* StrExt::split
* StrExt::splitn
* StrExt::split_terminator
* StrExt::rsplitn
* StrExt::match_indices
* StrExt::split_str
* StrExt::starts_with
* StrExt::ends_with
* StrExt::trim_chars
* StrExt::trim_left_chars
* StrExt::trim_right_chars
* StrExt::find
* StrExt::rfind
* StrExt::find_str
* StrExt::subslice_offset

Author: bors

src/compiletest/compiletest.rs

@@ -152,7 +152,7 @@ pub fn parse_config(args: Vec<String> ) -> Config {
             matches.opt_str("ratchet-metrics").map(|s| Path::new(s)),
         ratchet_noise_percent:
             matches.opt_str("ratchet-noise-percent")
-                   .and_then(|s| from_str::<f64>(s.as_slice())),
+                   .and_then(|s| s.as_slice().parse::<f64>()),
         runtool: matches.opt_str("runtool"),
         host_rustcflags: matches.opt_str("host-rustcflags"),
         target_rustcflags: matches.opt_str("target-rustcflags"),
@@ -190,9 +190,7 @@ pub fn log_config(config: &Config) {
     logv(c, format!("filter: {}",
                     opt_str(&config.filter
                                    .as_ref()
-                                   .map(|re| {
-                                       re.to_string().into_string()
-                                   }))));
+                                   .map(|re| re.to_string()))));
     logv(c, format!("runtool: {}", opt_str(&config.runtool)));
     logv(c, format!("host-rustcflags: {}",
                     opt_str(&config.host_rustcflags)));

src/compiletest/header.rs

@@ -351,8 +351,8 @@ pub fn gdb_version_to_int(version_string: &str) -> int {
         panic!("{}", error_string);
     }
 
-    let major: int = from_str(components[0]).expect(error_string);
-    let minor: int = from_str(components[1]).expect(error_string);
+    let major: int = components[0].parse().expect(error_string);
+    let minor: int = components[1].parse().expect(error_string);
 
     return major * 1000 + minor;
 }
@@ -362,6 +362,6 @@ pub fn lldb_version_to_int(version_string: &str) -> int {
         "Encountered LLDB version string with unexpected format: {}",
         version_string);
     let error_string = error_string.as_slice();
-    let major: int = from_str(version_string).expect(error_string);
+    let major: int = version_string.parse().expect(error_string);
     return major;
 }

src/compiletest/runtest.rs

@@ -1361,7 +1361,7 @@ fn split_maybe_args(argstr: &Option<String>) -> Vec<String> {
             s.as_slice()
              .split(' ')
              .filter_map(|s| {
-                 if s.is_whitespace() {
+                 if s.chars().all(|c| c.is_whitespace()) {
                      None
                  } else {
                      Some(s.to_string())

src/doc/guide.md

@@ -2257,10 +2257,10 @@ a function for that:
 let input = io::stdin().read_line()
                        .ok()
                        .expect("Failed to read line");
-let input_num: Option<uint> = from_str(input.as_slice());
+let input_num: Option<uint> = input.parse();
 ```
 
-The `from_str` function takes in a `&str` value and converts it into something.
+The `parse` function takes in a `&str` value and converts it into something.
 We tell it what kind of something with a type hint. Remember our type hint with
 `random()`? It looked like this:
 
@@ -2279,8 +2279,8 @@ In this case, we say `x` is a `uint` explicitly, so Rust is able to properly
 tell `random()` what to generate. In a similar fashion, both of these work:
 
 ```{rust,ignore}
-let input_num = from_str::<uint>("5");       // input_num: Option<uint>
-let input_num: Option<uint> = from_str("5"); // input_num: Option<uint>
+let input_num = "5".parse::<uint>();         // input_num: Option<uint>
+let input_num: Option<uint> = "5".parse();   // input_num: Option<uint>
 ```
 
 Anyway, with us now converting our input to a number, our code looks like this:
@@ -2301,7 +2301,7 @@ fn main() {
     let input = io::stdin().read_line()
                            .ok()
                            .expect("Failed to read line");
-    let input_num: Option<uint> = from_str(input.as_slice());
+    let input_num: Option<uint> = input.parse();
 
     println!("You guessed: {}", input_num);
 
@@ -2350,7 +2350,7 @@ fn main() {
     let input = io::stdin().read_line()
                            .ok()
                            .expect("Failed to read line");
-    let input_num: Option<uint> = from_str(input.as_slice());
+    let input_num: Option<uint> = input.parse();
 
     let num = match input_num {
         Some(num) => num,
@@ -2395,7 +2395,7 @@ Uh, what? But we did!
 
 ... actually, we didn't. See, when you get a line of input from `stdin()`,
 you get all the input. Including the `\n` character from you pressing Enter.
-Therefore, `from_str()` sees the string `"5\n"` and says "nope, that's not a
+Therefore, `parse()` sees the string `"5\n"` and says "nope, that's not a
 number; there's non-number stuff in there!" Luckily for us, `&str`s have an easy
 method we can use defined on them: `trim()`. One small modification, and our
 code looks like this:
@@ -2416,7 +2416,7 @@ fn main() {
     let input = io::stdin().read_line()
                            .ok()
                            .expect("Failed to read line");
-    let input_num: Option<uint> = from_str(input.as_slice().trim());
+    let input_num: Option<uint> = input.trim().parse();
 
     let num = match input_num {
         Some(num) => num,
@@ -2491,7 +2491,7 @@ fn main() {
         let input = io::stdin().read_line()
                                .ok()
                                .expect("Failed to read line");
-        let input_num: Option<uint> = from_str(input.as_slice().trim());
+        let input_num: Option<uint> = input.trim().parse();
 
         let num = match input_num {
             Some(num) => num,
@@ -2566,7 +2566,7 @@ fn main() {
         let input = io::stdin().read_line()
                                .ok()
                                .expect("Failed to read line");
-        let input_num: Option<uint> = from_str(input.as_slice().trim());
+        let input_num: Option<uint> = input.trim().parse();
 
         let num = match input_num {
             Some(num) => num,
@@ -2621,7 +2621,7 @@ fn main() {
         let input = io::stdin().read_line()
                                .ok()
                                .expect("Failed to read line");
-        let input_num: Option<uint> = from_str(input.as_slice().trim());
+        let input_num: Option<uint> = input.trim().parse();
 
         let num = match input_num {
             Some(num) => num,
@@ -2697,7 +2697,7 @@ fn main() {
         let input = io::stdin().read_line()
                                .ok()
                                .expect("Failed to read line");
-        let input_num: Option<uint> = from_str(input.as_slice().trim());
+        let input_num: Option<uint> = input.trim().parse();
 
         let num = match input_num {
             Some(num) => num,

src/doc/reference.md

@@ -3177,7 +3177,7 @@ Some examples of call expressions:
 # fn add(x: int, y: int) -> int { 0 }
 
 let x: int = add(1, 2);
-let pi: Option<f32> = from_str("3.14");
+let pi: Option<f32> = "3.14".parse();
 ```
 
 ### Lambda expressions

src/libcollections/lib.rs

@@ -121,15 +121,15 @@ mod prelude {
     // in core and collections (may differ).
     pub use slice::{PartialEqSliceExt, OrdSliceExt};
     pub use slice::{AsSlice, SliceExt};
-    pub use str::{from_str, Str, StrPrelude};
+    pub use str::{from_str, Str};
 
     // from other crates.
     pub use alloc::boxed::Box;
     pub use unicode::char::UnicodeChar;
 
     // from collections.
     pub use slice::{CloneSliceExt, VectorVector};
-    pub use str::{IntoMaybeOwned, UnicodeStrPrelude, StrAllocating, StrVector};
+    pub use str::{IntoMaybeOwned, StrVector};
     pub use string::{String, ToString};
     pub use vec::Vec;
 }