C++ for anything graphics-related, C# for anything else.
Your Prototyping Language?
I find it easier to manipulate with ideas in Lua. Once solution is crystal clear - it might be "baked" in c++.
I tend to use to prototype using the language of the project. So work related things are prototyped in C# and personal things either in C++, Python or Bash (what can I say, I am a linux guy :P).
When I don't have to write a prototype for some kind of visual problem, I will us unittests to ensure my code is correct.
When I am using C# and I only have to show some data, or try out some library to get it for me, I will use LinqPad, a program that makes it possible to use C# like a scripting languages... I haven't found anything like that for C++ though...
Even for learning parts of a language I will write unittests to make sure I understand how the language works...
, I will use LinqPad, a program that makes it possible to use C# like a scripting languages
So, wait, what does LinqPad let you do?
So, wait, what does LinqPad let you do?
It's basically just a REPL for .NET - let's you execute C# snippets in the editor, etc.