first attempt at implementing %p for fmt!

[minhnhdo]

pull request for #8011

[minhnhdo]

I don't know how to add a test for pointer address printing. Could you give me an example?

I have a program to try out the new functionality. The outputs are in the 0x7fxxxxxxx7a0 range, so I think it's sensible.

fn main() {
    let a = &1;
    println(fmt!("%p", a));
}

[huonw]

@mrordinaire maybe something like:

for 10.times {
    let x: uint = std::rand::random();
    assert_eq!(fmt!("%p", x as *uint), fmt!("%x", x));
}

[minhnhdo]

@huonw Thanks a bunch

[jdm]

Great! Would you mind rebasing and squashing all of these into one commit with a commit message that describes the overall change now? See http://gitready.com/advanced/2009/02/10/squashing-commits-with-rebase.html if you've never done this before.

[minhnhdo]

@alexcrichton hi, I don't think the failures are caused by my changes (except for the test code, whose cause is missing stdlib on windows). What should I do next?

[huonw]

@mrordinaire #6330, you either need ::std::rand::random(), or (preferably) just use std::rand; at the top of the file and then rand::random().

[minhnhdo]

@alexcrichton r?