The Ping Plan

[Aaron Swartz]

I was at dinner at CFP with Ka-Ping Yee, Brad Templeton, and a
Markdown user whose name I've forgotten (really sorry!). Ka-Ping had a
complaint which I finally realized would be solved by making things in
brackets work without additional syntax. Basically, he wanted this
common idiom to work:

    Foo bar baz.[1]
    
    [1]: http://lfw.org/

Which just happens to work if we implement this:

    [The President] is a miserable failure.
    
    [The President]: http://whitehouse.gov/

So that's good. He also wanted the :s to be optional, so this would work:

    Foo bar baz.[1]
    
    [1] http://lfw.org/

Finally, he wanted links to work without angle brackets, so this would work:

    Hey, check out Jon's website at http://www.jontheman.info

If, for some reason I can't think of, really wanted that not to be a
link but didn't want to put it inside `<code>` tags, you could do:

    Hey, check out Jon's website at \http://www.jontheman.info

(\h is a little weird, sure, but so is the request)

I don't see why any of these wouldn't work; other than the first,
they're all pretty unambiguous.

 - Aaron