Fastest prototyping language?

I want to write programs as fast as I can. Which language should I learn?

Using program length as a rough indicator, Forth is the choice. Samples I've seen like web servers, operating systems, database managers, etc. are significantly shorter in Forth.

But I've seen some really short Perl and Haskell routines too.

And Lisp is supposed to allow you to work at such high levels of abstraction that it should also make short applications.

Ruby gets a lot of comments about short line counts compared to Perl and Python.

Assuming
   -identical toolset library functionality,
   -maximum expertise in all the candidate languages
   -no concern of readability, "transparent" design, or 
    execution speed
which language syntax will allow you to write your program fastest?

In b4 machine code.

>>53
You've caught me in my serious day, I'm serious Anonymous and this is serious post. I'll propose Python, but I'll comment on its pros and cons here.

Of these 3 families, the S-expression seems best for fast prototyping
I'd say this family seems best for anything (at least anything that's real work). Real work requires changes (it mostly is made of changes) and you need to take as little time as possible, and want as much flexibility as possible.

I favour Python as a practical language, yet here's my main gripe with it: it has statements.

FFI
Python has awesome FFI. It has ctypes, which is simple and what you need, but you mentioned Win32 programming. Python also has PyWin32, which takes an extra step and makes it a bit more Python-friendly, function by function (so it's XBOX), and you may want to have a look at it as well. You also said something about GUIs. Python is probably the best of the languages you're considering here. Not only it supports Win32 (either natively or through FFI), but it also supports WxWidgets, Qt, GTK, Tk, and god knows what else (I've even seen custom small UIs on top of SDL+OpenGL), as well as several console interfaces (try Urwid, looks awesome).

CPAN
Just Python's standard library is a pretty decent contender as it's packed with all kinds of useful stuff, from SQLite to an SGML parser. Then you have the Python Cheese Shop, which is not as large as CPAN, but has good stuff.