instance_exec routes -> form helpers

The new router in Rails 3 is clean and concise and marks the
acceptance of instance_exec as a method for writing a gorgeous DSL.

I'm wondering should something similar be applied to the default form helpers?

Moving from this:

<%= form_for(@post) do |f| %>
  <%= f.text_field :title %>
<% end %>

to this:

<%= form_for(@post) do %>
  <%= text_field :title %>
<% end %>


I tried it earlier just to check and kind of expected that it _might_
already have been implemented.

I don't know much about the implementation details, other than that
it's possible to do but requires a bit of magic, but I feel like it
might be something worth considering.


The biggest problem with the instance_exec version is that it's pretty
ugly if you actually need to pass the helper object into, for
instance, a partial. Not really relevant for the router, but *very*
relevant for form builders...

--Matt Jones