C#

[ServiceContract(Namespace = "http://www.mycompany.com/product/2007/12")]

[ServiceContract(Namespace = "http://www.mycompany.com/product/2008/08")]

struct myStruct { ... }

List<myStruct?> list;

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I'm largely language agnostic

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After a while they all bug me

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int? myNullableInt = null;

List<int?> myNullableIntList = new List<int?>;

struct myStruct {
 public bool IsValid;
 public readonly myStruct Empty; // all members are in a valid 'empty' state.
}

foreach(myStruct? item in collection) {
 if((item ?? myStruct.Empty).IsValid) {
  ...
 }
}

---

I'm largely language agnostic

---

After a while they all bug me

---

int? myInt; // to
Nullable<int> myInt;

public struct X
{
    private string m_Property;
    public string Property
    {
        get { return m_Property; }
        set { m_Property = value; }
    }

}
public class XCollection : List<X>
{
    private bool ItemExists(string stringProperty)
    {

        X found = Find(item => item.Property == stringProperty);
        return found.Property != null ? true : false;
    }
}