New attribute layout

When clicking Attribute, the window changes to the attribute layout. It has the following components:


This dialog box:

Produces this feature:
class PRODUCT feature {NONE} -- Access price: DOUBLE -- Cost in dollars. feature -- Element change set_price (a_price: DOUBLE) -- Assign `a_price' to `price'. require a_price_non_negative: a_price >= 0.0 do price := a_price ensure price_assigned: price = a_price end invariant price_non_negative: price >= 0.0 end -- class PRODUCT