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.

Haskell is the worst possible language for prototyping. It requires you to plan out every tiny little faggot detail of the program before you write it, and if you make a design error early on in a haskell project it's almost impossible to go back and change it because of the type system. It was a language designed by academics so that they have something to write papers to about (and boy, have they capitalized).