Does Foreach Cache IEnumerable?

Question

Supposing that SomeMethod has signature

public IEnumerable SomeMethod();

is there any difference between

Answer 1

Assuming you're talking about C#.

foreach translates into something like this:

var enumerable = SomeMethod(); // Or whatever is passed to foreach
var enumerator = enumerable.GetEnumerator();

while (enumerator.MoveNext())
{
...
}

So, as enumerable is needed only once, there will be only one call to SomeMethod even if you put it directly into the foreach statement.