What is the Purpose of Closures?

I really don't understand what the purpose of closures is. It seems to me that everything that can be written using closures, is just as easily written without. For example:


void main()
{
    int[] haystack = [345,15,457,9,56,123,456];
    int   needle = 123;
    bool needleTest(int n)
    {
        return n == needle;
    }
    printf(find(haystack, &needleTest));
}

Wouldn't this be better written as:


void main()
{
    int[] haystack = [345,15,457,9,56,123,456];
    int   needle = 123;
    foreach(int i : haystack)
    {
        if (i == needle)
        {
            printf(i);
        }
    }
}

Or at least defining the function outside of main() and referencing it inside? I just don't understand the benefit of closures.

>>28
I think it's because humans have generally used base 10 as a counting system (though there are some notable exceptions), due to the fact that they have 10 fingers. It makes sense, then, that any programming language designed by humans will use base ten. There is, however, notational support in D for base 2, base 8, and base 16 numbers.