Slashdot said that programming has a political axis with conservative and liberal programmers. Liberal programmers worry about how fast you take to implement a feature. Liberal programmers need the answer to this question. (1)<p>Paul Graham said that his company could implement features faster than his competitors, because his company programmed in Common Lisp and Common Lisp makes you twice more productive as a programmer. (2)<p>Time passes, progress happens, Common Lisp <i>was</i> the fastest, a more modern programming language <i>is</i> the fastest, so <i>today</i> what programming language is the fastest to implement features? Why?<p>(1) http://slashdot.org/index2.pl?fhfilter=political+axis
(2) http://www.paulgraham.com/avg.html
Must we use this 'liberal' vs. 'conservative' language for programming styles? The terms are already so ridiculously value-laden, you're at risk of letting your political leanings involuntarily bleed through and muddle up your programming decisions.
There is no objective way to answer this. You are probably talking about rapid prototyping languages. The most popular ones in use today are Python and possibly Java (?). Dialects of Lisp have a strong tradition of being good rapid prototyping languages and there is potential in languages like Haskell. I'm obviously talking about general purpose languages here and therein lies the problem. Different languages have different resources, different communities and perform better at different tasks. It not possible to go in more detail. However this is not a question that you should be asking yourself because the answer will come naturally with time. Try to experience and learn as much and with time you'll have a preference for a language when you just want to hack something together. That's your answer.
Productivity depends way more on the programmer and his/her knowledge of the common idioms, language features, and libraries for any particular platform than any specific language. The characteristics of languages that make it fast to implement features include dynamic typing, built-in collections, a large class library, availability of an interactive console, availability of a debugger that can easily be used on any host machine, JIT compiled or interpreted, no binaries or packages to build.
If you want a quick and dirty CRUD app, GeneXus is probably up there:<p><a href="http://www.genexus.com/global/home?en" rel="nofollow">http://www.genexus.com/global/home?en</a><p>It's a code generation tool that's mainly popular in South America and is making some inroads in Japan and Europe.<p>It does generate some ugly code, and ugly-looking applications, but it generates all the backend code and can generate to iOS and Android too.
It sounds like you might be asking about what's often called "rapid prototyping". That doesn't cover every possible case (e.g. adding a new feature to a large existing system is not usually covered by "rapid prototyping"), but I think it points to the languages that tend to emphasize ease-of-getting-something-out. Python and Ruby are often promoted in that category. Delphi used to be big, but is waning.