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C # object looks like a dynamic type

We played with 4.0 DLR and compared the dynamics with the object and came across this:

the code:

object x = 10;
            Console.WriteLine("x = {0} and is a {1}.\n", x, x.GetType());
            x = (int)x + 3;
            Console.WriteLine("x = {0} and is a {1}.\n", x, x.GetType());
            x = x + "a";
            Console.WriteLine("x = {0} and is a {1}.\n", x, x.GetType());

Result:

x = 10 and is System.Int32.

x = 13 and is System.Int32.

x = 13a and is System.String.

It seems to me that the object is trying to bind the object to a type at runtime (dynamic). However, if I don't pass x to int on the third line, this gives me a compiler area that seems correct for static input. But then it lets me add "a" to x, and now it recognizes it as a string.

What am I missing?

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7 answers

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  IL_0000:  nop
  IL_0001:  ldc.i4.s   10
  IL_0003:  box        [mscorlib]System.Int32
  IL_0008:  stloc.0
  IL_0009:  ldloc.0
  IL_000a:  ldstr      "a"
  IL_000f:  call       string [mscorlib]System.String::Concat(object,
                                                              object)

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# 5.0 :

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