Simplified for loop

[wojciechsura]

I'm proposing a simplified for loop in cases that something needs to be done x times, but we don't care about the iterator.

Let's consider the following scenario:

int count = binaryReader.ReadInt32();
for (int i = 0; i < count; i++)
{
    // Read i-th entry
}

The simplified notation would allow the following:

int count = binaryReader.ReadInt32();
for (count)
{
    // Read entry
}

Rationale:
For loop is used if we care about the index of processed item. Foreach loop is used if we care about the processed item. However, there is no option if we only care about certain number of executions.
This is a syntax simplification on the same level as e.g. simplifying using statements so that they don't require braces if their scope equals to enclosing scope.

Alternative:
Not too many. The only one that comes to my mind is:

foreach (var _ in Enumerable.Range(0, count))
{

}

However, this one is even longer than a regular for loop.

[huoyaoyuan]

Covered in #2810.

The use case is concrete, we can discuss for the syntax later.

Moreover, if the iteration count is constant, the compiler (roslyn or JIT) can choose to unroll it.