Handle all primitive types.

[JohanLarsson]

• System.BigInteger
• System.Boolean
• System.Byte
• System.Char
• System.DateTime
• System.DateTimeOffset
• System.Decimal
• System.Double
• System.Enum ([Flags])
• System.Guid
• System.Int16
• System.Int32
• System.Int64
• System.IntPtr
• System.Object
• System.SByte
• System.Single
• System.String
• System.TimeSpan
• System.UInt16
• System.UInt32
• System.UInt64
• System.UIntPtr
• System.Url

Specification: https://www.w3.org/TR/xmlschema-2/

[JohanLarsson]

[TestCase('a')]
[TestCase('\t')]
public void Char(char value)
{
    var with = new WithMutable<char> { Value = value };
    var actual = Xml.Serialize(with);
    var expected = Reference.Xml(with);
    Assert.AreEqual(expected, actual);
}

[jnm2]

Where would BigInteger fall in the grand scheme of things?

[jnm2]

IntPtr and UIntPtr are primitive types too, I think.

[jnm2]

Would byte[] as base64 be considered an XML primitive?

[JohanLarsson]

@jnm2 how would you like the defaults for serializing DateTime & DateTimeOffset? I'm thinking UTC and ISO8601 as default.

[jnm2]

ISO 8601 would be my preference.