Understanding how the C # compiler deals with binding linq methods

Question

I am trying to wrap what the C # compiler does when I chain linq methods, especially when repeatedly connecting the same method.

A simple example: . Let's say I'm trying to filter out an int sequence based on two conditions.

The most obvious thing to do is something like this:

IEnumerable<int> Method1(IEnumerable<int> input)
{
    return input.Where(i => i % 3 == 0 && i % 5 == 0);
}

But we could also associate the where methods with one condition in each:

IEnumerable<int> Method2(IEnumerable<int> input)
{
    return input.Where(i => i % 3 == 0).Where(i => i % 5 == 0);
}

I looked at IL in Reflector; it is clearly different for the two methods, but its analysis is not further clear at the moment :)

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b) - ( -, !)

Answer 1

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Answer 2

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