[racket-dev] Feature suggestion

Over the past few months, I've had to spend a lot of time in Visual
Studio (no comments from the
peanut gallery, please!).  It has a feature that might be useful in
DrRacket.  When you enter a
class or class instance name followed by a dot, you get a popup of
valid methods.  Yes, DrRacket
has the name completion feature.  But after you enter one of the VS
method names and an open
paren, you get a signature (or often, many signatures due to a
maddening number of overloads).
As you type in arguments, the relevant part of the signature becomes
bold-faced.

You really get addicted to this setup -- see the article "Does Visual
Studio Rot the Mind?" by
Charles Petzold.

Currently, DrRacket offers name completion and the ability to lookup
names in Help Desk.
That works, but it's a bit ungainly.  It would be ne plus ultra cool
if when you entered

  (some-fun

you got a popup with the arguments to be entered.   If `some-fun' is
in Help Desk, their arguments
could have their names and types.  If `some-fun' is defined in the
current file or require'd, you'd
just have the argument names.  Ambitiously, if the argument had a
corresponding predicate in a
contract, you could show that.

-- Paul