C# immutable int

Question

In Java strings are immutable. If we have a string and make changes to it, we get new string referenced by the same variable:

String str = \"abc\";
str += \"def\         


        

Answer 1

You haven't changed (and cannot change) something about the int; you have assigned a new int value (and discarded the old value). Thus it is immutable.

Consider a more complex struct:

var x = new FooStruct(123);
x.Value = 456; // mutate
x.SomeMethodThatChangedInternalState(); // mutate

x = new FooStruct(456); // **not** a mutate; this is a *reassignment*

However, there is no "pointing" here. The struct is directly on the stack (in this case): no references involved.