Documentation ¶
Index ¶
- type Und
- func (u Und[T]) Clone() Und[T]
- func (u Und[T]) DoublePointer() **T
- func (u Und[T]) Equal(other Und[T]) bool
- func (u Und[T]) IsDefined() bool
- func (u Und[T]) IsNull() bool
- func (u Und[T]) IsUndefined() bool
- func (u Und[T]) IsZero() bool
- func (o Und[T]) LogValue() slog.Value
- func (u Und[T]) Map(f func(option.Option[option.Option[T]]) option.Option[option.Option[T]]) Und[T]
- func (u Und[T]) MarshalJSON() ([]byte, error)
- func (u Und[T]) MarshalJSONV2(enc *jsontext.Encoder, opts jsonv2.Options) error
- func (o Und[T]) MarshalXML(e *xml.Encoder, start xml.StartElement) error
- func (u Und[T]) Pointer() *T
- func (o Und[T]) SqlNull() sql.Null[T]
- func (u *Und[T]) UnmarshalJSON(data []byte) error
- func (u *Und[T]) UnmarshalJSONV2(dec *jsontext.Decoder, opts jsonv2.Options) error
- func (o *Und[T]) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error
- func (u Und[T]) Unwrap() option.Option[option.Option[T]]
- func (u Und[T]) Value() T
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Und ¶
type Und[T any] struct { // contains filtered or unexported fields }
Und[T] is a type that can express a value (`T`), empty (`null`), or absent (`undefined`). Und[T] is comparable if T is comparable. And it can be copied by assign.
Und[T] implements IsZero and can be skippable struct fields when marshaled through appropriate marshalers, e.g. "github.com/go-json-experiment/json/jsontext" with omitzero option set to the field, or "github.com/json-iterator/go" with omitempty option to the field and an appropriate extension.
If you need to stick with encoding/json v1, you can use github.com/ngicks/und/sliceund, a slice based version of Und[T] whish is already skppable by v1.
func FromOption ¶
FromOptions converts opt into an Und[T]. opt is retained by the returned value.
func FromPointer ¶
FromPointer converts *T into Und[T]. If v is nil, it returns an undefined Und. Otherwise, it returns Defined[T] whose value is the dereferenced v.
func FromSqlNull ¶
FromSqlNull converts a valid sql.Null[T] to a defined Und[T] and invalid one into a null Und[].
func (Und[T]) DoublePointer ¶
func (u Und[T]) DoublePointer() **T
DoublePointer returns nil if u is undefined, &(*T)(nil) if null, the internal value if defined.
func (Und[T]) Equal ¶
Equal implements Equality[Und[T]]. Equal panics if T is uncomparable and does not implement Equality[T].
func (Und[T]) IsUndefined ¶
IsUndefined returns true if u is an undefined value, otherwise false.
func (Und[T]) MarshalJSON ¶
MarshalJSON implements json.Marshaler.
func (Und[T]) MarshalJSONV2 ¶
MarshalJSONV2 implements jsonv2.MarshalerV2.
func (Und[T]) MarshalXML ¶
MarshalXML implements xml.Marshaler.
func (Und[T]) Pointer ¶
func (u Und[T]) Pointer() *T
Pointer returns u's internal value as a pointer.
func (*Und[T]) UnmarshalJSON ¶
UnmarshalJSON implements json.Unmarshaler.
func (*Und[T]) UnmarshalJSONV2 ¶
UnmarshalJSONV2 implements jsonv2.UnmarshalerV2.
func (*Und[T]) UnmarshalXML ¶
UnmarshalXML implements xml.Unmarshaler.