Improve documentation for core::io.

This commit is contained in:
Steve Klabnik 2013-04-01 16:37:40 -07:00
parent dc60788215
commit a20d1ad0cb

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@ -49,29 +49,89 @@ pub mod rustrt {
// FIXME (#2004): This is all buffered. We might need an unbuffered variant
// as well
/**
* The SeekStyle enum describes the relationship between the position
* we'd like to seek to from our current position. It's used as an argument
* to the `seek` method defined on the `Reader` trait.
*
* There are three seek styles:
*
* 1. `SeekSet` means that the new position should become our position.
* 2. `SeekCur` means that we should seek from the current position.
* 3. `SeekEnd` means that we should seek from the end.
*
* # Examples
*
* None right now.
*/
pub enum SeekStyle { SeekSet, SeekEnd, SeekCur, }
/// The raw underlying reader trait. All readers must implement this.
/**
* The core Reader trait. All readers must implement this trait.
*
* # Examples
*
* None right now.
*/
pub trait Reader {
// FIXME (#2004): Seekable really should be orthogonal.
/// Read up to len bytes (or EOF) and put them into bytes (which
/// must be at least len bytes long). Return number of bytes read.
// FIXME (#2982): This should probably return an error.
/**
* Reads bytes and puts them into `bytes`. Returns the number of
* bytes read.
*
* The number of bytes to be read is `len` or the end of the file,
* whichever comes first.
*
* The buffer must be at least `len` bytes long.
*
* # Examples
*
* None right now.
*/
fn read(&self, bytes: &mut [u8], len: uint) -> uint;
/// Read a single byte, returning a negative value for EOF or read error.
/**
* Reads a single byte.
*
* In the case of an EOF or an error, returns a negative value.
*
* # Examples
*
* None right now.
*/
fn read_byte(&self) -> int;
/// Return whether the stream is currently at EOF position.
/**
* Returns a boolean value: are we currently at EOF?
*
* # Examples
*
* None right now.
*/
fn eof(&self) -> bool;
/// Move the current position within the stream. The second parameter
/// determines the position that the first parameter is relative to.
/**
* Seek to a given `position` in the stream.
*
* Takes an optional SeekStyle, which affects how we seek from the
* position. See `SeekStyle` docs for more details.
*
* # Examples
*
* None right now.
*/
fn seek(&self, position: int, style: SeekStyle);
/// Return the current position within the stream.
/**
* Returns the current position within the stream.
*
* # Examples
*
* None right now.
*/
fn tell(&self) -> uint;
}