metaprogram c++ code

New semester in my university started and I am once again "forced" to quit abstractions and explore the deep waters of low level programming in c++. My mind is already partiall开发者_如何学Pythony contamined with folds, high order functions, etc., and I don't find any fun in writing for example:

bool allEven = true;
for(int i = 0; i < arr.length; i++){
   if (arr[i] % 2 != 0){
      allEven = false; 
      break;
   }
}

when I know that I can write val allEven = arr forall (_ % 2 == 0).

My question is: is there any tool|technique|language construct|metaprogramming stuff, that can bring some c++ code without writing it actually? I need to the whole source but it can be eventually obfuscated, only machine is going to process it.

And please don't me accuse of being lazy, I value it as one of my best virtues. :-)

EDIT It's not entirely clear what are you asking for... At best, I would like to use something like GWT but instead compiling Java sources to JavaScript sources It would compile Scala or Haskell or F# to C++ sources, but since I don't believe that something like this exists, I would like to have something... helpful. I appreciate the suggested anon functions, for example.

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It's not entirely clear what you're really asking for, but if you're trying to write C++ that's more like your other code, you could do something like this:

bool allEven = 
    std::accumulate(arr.begin(), arr.end(), [](bool a, int i) {return a && i & 1==0; }, 1);

This does use a lambda, which is new in C++0x. If you're using an older compiler that doesn't support lambdas, you could look into using Boost Lambda instead (in which case your code would be even closer to the example you've given).

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bool is_even = std::find_if(arr.begin(), arr.end(), [](int i) { return i%2 != 0; }) == arr.end();

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With new algorithms in C++0x, there is all_of:

bool all_even = std::all_of(arr.begin(), arr.end(),
                            [](int i) { return i%2 == 0; });

Boost.Range allows less verbosity:

bool all_even = 
    0==boost::count_if(arr, [](int i){ return i%2 != 0;});

Hopefully, Boost.Range will soon offer all_of.

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Take a look at Boost.Phoenix library, it enables you to write close(er) to functional style of programming in C++.