/// <summary>
/// Gets if the two values are equal.
/// </summary>
/// <param name="other">
/// The compared value.
/// </param>
/// <returns>
/// returns <c>true</c> if
///
/// The two values are both existing or missing
/// and inner values are equal with the default comparer.
/// </returns>
public bool Equals(Opt <T> other)
{
if (!IsSome)
{
return(!other.IsSome);
}
return(other.IsSome && EqualityComparer <T> .Default.Equals(Value, other.Value));
}
public void SomeHasValue()
{
var some1 = Opt.Some(1);
some1.IsSome
.Is(true);
some1.Value
.Is(1);
}
public void NoneHasNoValue()
{
var none = Opt.None <int>();
none.IsSome
.Is(false);
Assert.Throws <InvalidOperationException>(() =>
Opt.None <string>().Value
);
}
/// <summary>
/// Compare the two values.
///
/// <c>None</c>s are lesser than <c>Some</c>s.
/// </summary>
public int CompareTo(Opt <T> other)
{
if (!IsSome)
{
return(other.IsSome ? 0 : 1);
}
if (!other.IsSome)
{
return(-1);
}
return(Comparer <T> .Default.Compare(Value, other.Value));
}
public void ItMapsNoneToNestedSome()
{
Opt.AllowNull(Opt.None <int>())
.Is(Opt.Some(Opt.None <int>()));
}
public void ItMapsNonnullDefaultToSome()
{
Opt.AllowNull(default(int))
.Is(Opt.Some(0));
}
public void ItMapsNonnullToSome()
{
Opt.AllowNull("not null")
.Is(Opt.Some("not null"));
}
public void ItMapsNullStructToNone()
{
Opt.AllowNull((int?)null)
.Is(Opt.None <int>());
}
public void ItMapsNullReferenceToNone()
{
Opt.AllowNull((string)null)
.Is(Opt.None <string>());
}
public void SomeRejectsNull()
{
Assert.Throws <ArgumentNullException>(() =>
Opt.Some((string)null)
);
}
public Field(Opt <T> defaultValue, int index)
{
DefaultValue = defaultValue;
Index = index;
}