Table of Contents

Class ValueBox

Namespace
The.Persistence
Assembly
Instagile.dll

ValueBox wraps an object which is one of the finite The.Values types.

[MessagePackObject(false)]
[JsonPolymorphic(TypeDiscriminatorPropertyName = "$")]
[Union(0, typeof(BoolBox))]
[JsonDerivedType(typeof(BoolBox), 0)]
[Union(1, typeof(ByteBox))]
[JsonDerivedType(typeof(ByteBox), 1)]
[Union(2, typeof(DateBox))]
[JsonDerivedType(typeof(DateBox), 2)]
[Union(3, typeof(DateTimeBox))]
[JsonDerivedType(typeof(DateTimeBox), 3)]
[Union(4, typeof(DecBox))]
[JsonDerivedType(typeof(DecBox), 4)]
[Union(5, typeof(DoubleBox))]
[JsonDerivedType(typeof(DoubleBox), 5)]
[Union(6, typeof(GuidBox))]
[JsonDerivedType(typeof(GuidBox), 6)]
[Union(7, typeof(InstantBox))]
[JsonDerivedType(typeof(InstantBox), 7)]
[Union(8, typeof(IntBox))]
[JsonDerivedType(typeof(IntBox), 8)]
[Union(9, typeof(LongBox))]
[JsonDerivedType(typeof(LongBox), 9)]
[Union(10, typeof(StringBox))]
[JsonDerivedType(typeof(StringBox), 10)]
[Union(11, typeof(TimeBox))]
[JsonDerivedType(typeof(TimeBox), 11)]
[Union(12, typeof(PeriodBox))]
[JsonDerivedType(typeof(PeriodBox), 12)]
[Union(13, typeof(VersionBox))]
[JsonDerivedType(typeof(VersionBox), 13)]
public abstract class ValueBox : IComparable
Inheritance
ValueBox
Implements
Derived
Inherited Members

Remarks

Many serialisation formats are based roughly on the JSON primitives: object, array, string, number, boolean. This model is flexible but it has a few problems for working with dynamic data:

  1. can't differentiate between numeric types (int vs long, float vs double vs decimal, sometimes all of the above are combined)
  2. no encoding for composite value types (guid, timespan, or most generally: byte array)
  3. dates are encoded in many different incompatible ways, even by .NET itself
  4. some serialisers can't handle too much dynamism, e.g. object-which-might-be-null-or-primitive

To avoid these problems, we replace CLR boxing with an explicit discriminated union.

Methods

Box(object?) 

public static ValueBox? Box(object? o)

Parameters

o object

Returns

ValueBox

CompareTo(object?)

Compares the current instance with another object of the same type and returns an integer that indicates whether the current instance precedes, follows, or occurs in the same position in the sort order as the other object.

public abstract int CompareTo(object? other)

Parameters

other object

Returns

int

A value that indicates the relative order of the objects being compared. The return value has these meanings:

Value Meaning
Less than zero This instance precedes obj in the sort order.
Zero This instance occurs in the same position in the sort order as obj.
Greater than zero This instance follows obj in the sort order.

Exceptions

ArgumentException

obj is not the same type as this instance.

Type(Type) 

public static TypeBox Type(Type type)

Parameters

type Type

Returns

TypeBox

Unbox(ValueBox?) 

public static object? Unbox(ValueBox? b)

Parameters

b ValueBox

Returns

object