arrow function syntax simplified

[Luke Hoban]

> >Luke Hoban wrote:
> > The do expressions serve a separate purpose of changing the meaning of return (but not break and continue)
> Dave proposed at
> https://mail.mozilla.org/pipermail/es-discuss/2012-March/021000.html
> that do expressions be fully TCP compliant. No way to be half-pregnant :-/.

True - I misspoke there.  The concern related to break and continue I had in mind was separate from what I noted - it is the issues raised at https://mail.mozilla.org/pipermail/es-discuss/2012-January/019525.html.  

But my primary point was just that in Rick's examples, there doesn't appear to be any reliance on TCP at all.  Had => supported blocks on the RHS as in the original arrow proposal, all the code samples would be simpler, simply removing the 'do'.  I believe this will generally be true too.  

Luke