io: code examples, un-xfail conditions tutorial

[adrientetar]

No description provided.

[huonw]

Why did you remove the for loop? That is more idiomatic.

[adrientetar]

The previous example is also from me but:

• it's a dupe of an example at the beginning of the file
• the documented function is .eof(), not .lines()

[huonw]

Oh... I'd personally prefer something very simple like:

let mut reader = ...;
println(reader.read_line());

if reader.eof() { println("only one line"); }

rather than encouraging the use of .eof() in places where there are better alternatives.

[huonw]

Probably best to do

use std::io;
let mut reader = io::stdin(); 

let mut bytes = [0, .. 10];
reader.read(..); 
if reader.eof() { println("..."); }

rather than call stdin() twice. (Since most other readers won't return the same instance if you create them twice; i.e. each File::open(path) creates a new file reader handle.)