Why can't I compare a KeyValuePair with default

Question

In .Net 2.5 I can usually get an equality comparison (==) between a value and its type default

if (myString == default(string))

However I g

Answer 1

It fails for the same reason as the following:

var kvp = new KeyValuePair("a","b");
var res = kvp == kvp;

The clue is in the error message, naturally. (It has nothing to do with default).

Operator '==' cannot be applied to operands of type 'System.Collections.Generic.KeyValuePair' and 'System.Collections.Generic.KeyValuePair'

The operator == is not defined for KeyValuePair.

Error messages FTW.

Happy coding.