libstd: Document the following modules:

* native::io
* std::char
* std::fmt
* std::fmt::parse
* std::io
* std::io::extensions
* std::io::net::ip
* std::io::net::udp
* std::io::net::unix
* std::io::pipe
* std::num
* std::num::f32
* std::num::f64
* std::num::strconv
* std::os

src/libstd/io/mod.rs

@@ -300,25 +300,45 @@ impl fmt::Show for IoError {
     }
 }
 
+/// A list specifying general categories of I/O error.
 #[deriving(Eq, Clone, Show)]
 #[allow(missing_doc)]
 pub enum IoErrorKind {
+    /// Any I/O error not part of this list.
     OtherIoError,
+    /// The operation could not complete because end of file was reached.
     EndOfFile,
+    /// The file was not found.
     FileNotFound,
+    /// The file permissions disallowed access to this file.
     PermissionDenied,
+    /// A network connection failed for some reason not specified in this list.
     ConnectionFailed,
+    /// The network operation failed because the network connection was cloesd.
     Closed,
+    /// The connection was refused by the remote server.
     ConnectionRefused,
+    /// The connection was reset by the remote server.
     ConnectionReset,
+    /// The connection was aborted (terminated) by the remote server.
     ConnectionAborted,
+    /// The network operation failed because it was not connected yet.
     NotConnected,
+    /// The operation failed because a pipe was closed.
     BrokenPipe,
+    /// A file already existed with that name.
     PathAlreadyExists,
+    /// No file exists at that location.
     PathDoesntExist,
+    /// The path did not specify the type of file that this operation required. For example,
+    /// attempting to copy a directory with the `fs::copy()` operation will fail with this error.
     MismatchedFileTypeForOperation,
+    /// The operation temporarily failed (for example, because a signal was received), and retrying
+    /// may succeed.
     ResourceUnavailable,
+    /// No I/O functionality is available for this task.
     IoUnavailable,
+    /// A parameter was incorrect in a way that caused an I/O error not part of this list.
     InvalidInput,
 }
 
@@ -1411,15 +1431,25 @@ pub struct FileStat {
 #[allow(missing_doc)]
 #[deriving(Hash)]
 pub struct UnstableFileStat {
+    /// The ID of the device containing the file.
     device: u64,
+    /// The file serial number.
     inode: u64,
+    /// The device ID.
     rdev: u64,
+    /// The number of hard links to this file.
     nlink: u64,
+    /// The user ID of the file.
     uid: u64,
+    /// The group ID of the file.
     gid: u64,
+    /// The optimal block size for I/O.
     blksize: u64,
+    /// The blocks allocated for this file.
     blocks: u64,
+    /// User-defined flags for the file.
     flags: u64,
+    /// The file generation number.
     gen: u64,
 }