elastic

Documentation

Index

• func UndValidate[T validate.UndValidator](e Elastic[T]) error
• type Elastic
  • func FromOptionSeq[T any](seq iter.Seq[option.Option[T]]) Elastic[T]
  • func FromOptions[T any](options ...option.Option[T]) Elastic[T]
  • func FromPointer[T any](t *T) Elastic[T]
  • func FromPointers[T any](ps ...*T) Elastic[T]
  • func FromUnd[T any, Opts ~[]option.Option[T]](u und.Und[Opts]) Elastic[T]
  • func FromValue[T any](t T) Elastic[T]
  • func FromValues[T any](ts ...T) Elastic[T]
  • func Map[T, U any](e Elastic[T], f func(t T) U) Elastic[U]
  • func Null[T any]() Elastic[T]
  • func Undefined[T any]() Elastic[T]
  • func WrapPointer[T any](t *T) Elastic[*T]
  • func WrapPointers[T any](ps ...*T) Elastic[*T]
  • func (e Elastic[T]) Clone() Elastic[T]
  • func (e Elastic[T]) Equal(other Elastic[T]) bool
  • func (e Elastic[T]) EqualFunc(other Elastic[T], cmp func(i, j T) bool) bool
  • func (e Elastic[T]) HasNull() bool
  • func (e Elastic[T]) IsDefined() bool
  • func (e Elastic[T]) IsNull() bool
  • func (e Elastic[T]) IsUndefined() bool
  • func (e Elastic[T]) IsZero() bool
  • func (e Elastic[T]) Iter() iter.Seq[option.Option[option.Options[T]]]
  • func (e Elastic[T]) Len() int
  • func (e Elastic[T]) LogValue() slog.Value
  • func (e Elastic[T]) Map(f func(und.Und[option.Options[T]]) und.Und[option.Options[T]]) Elastic[T]
  • func (u Elastic[T]) MarshalJSON() ([]byte, error)
  • func (e Elastic[T]) MarshalJSONV2(enc *jsontext.Encoder, opts jsonv2.Options) error
  • func (e Elastic[T]) MarshalXML(enc *xml.Encoder, start xml.StartElement) error
  • func (e Elastic[T]) PlainMultiple() []*T
  • func (e Elastic[T]) PlainSingle() *T
  • func (e Elastic[T]) Pointer() *T
  • func (e Elastic[T]) Pointers() []*T
  • func (e Elastic[T]) UndCheck() error
  • func (e Elastic[T]) UndValidate() error
  • func (e *Elastic[T]) UnmarshalJSON(data []byte) error
  • func (e *Elastic[T]) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error
  • func (e Elastic[T]) Unwrap() und.Und[option.Options[T]]
  • func (e Elastic[T]) Value() T
  • func (e Elastic[T]) ValueMultiple() []T
  • func (e Elastic[T]) ValueSingle() T
  • func (e Elastic[T]) Values() []T

Functions

func UndValidate

func UndValidate[T validate.UndValidator](e Elastic[T]) error

Types

type Elastic

type Elastic[T any] struct {
	// contains filtered or unexported fields
}

Elastic[T] is a type that can express undefined | null | T | [](null | T). Elastic[T] implements json.Unmarshaler so that it can be unmarshaled from all of those type. However it always marshaled into an array of JSON value that corresponds to T.

Elastic[T] implements IsZero and can be omittable 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/elastic, a slice based version of Elastic[T] whish is already skppable by v1.

func FromOptionSeq

func FromOptionSeq[T any](seq iter.Seq[option.Option[T]]) Elastic[T]

func FromOptions

func FromOptions[T any](options ...option.Option[T]) Elastic[T]

FromOptions converts variadic option.Option[T] values into Elastic[T]. options is retained by the returned value.

func FromPointer

func FromPointer[T any](t *T) Elastic[T]

FromPointer converts nil to undefined Elastic[T], or defined one whose internal value is dereferenced t.

If you need to keep t as pointer, use WrapPointer instead.

func FromPointers

func FromPointers[T any](ps ...*T) Elastic[T]

FromPointers converts variadic *T values into an Elastic[T], treating nil as None[T], and non-nil as Some[T].

If you need to keep t-s as pointer, use WrapPointers instead.

func FromUnd

func FromUnd[T any, Opts ~[]option.Option[T]](u und.Und[Opts]) Elastic[T]

FromUnd converts und.Und[option.Options[T]] into Elastic[T].

The internal value of u is retained by the returned value.

func FromValue

func FromValue[T any](t T) Elastic[T]

FromValue returns Elastic[T] with single some value.

func FromValues

func FromValues[T any](ts ...T) Elastic[T]

FromValues converts variadic T values into an Elastic[T].

func Map

func Map[T, U any](e Elastic[T], f func(t T) U) Elastic[U]

Map returns a new Elastic value whose internal value is mapped by f.

Be cautious that f will only be applied to some value; null values remain as null.

func Null

func Null[T any]() Elastic[T]

Null returns a null Elastic[T].

func Undefined

func Undefined[T any]() Elastic[T]

Undefined returns an undefined Elastic[T].

func WrapPointer

func WrapPointer[T any](t *T) Elastic[*T]

WrapPointer converts *T into Elastic[*T]. The elastic value is defined if t is non nil, undefined otherwise.

If you want t to be dereferenced, use FromPointer instead.

func WrapPointers

func WrapPointers[T any](ps ...*T) Elastic[*T]

FromPointers converts variadic *T values into an Elastic[*T], treating nil as None[*T], and non-nil as Some[*T].

If you need t-s to be dereferenced, use FromPointers instead.

func (Elastic[T]) Clone

func (e Elastic[T]) Clone() Elastic[T]

Clone implements option.Cloner[Elastic[T]].

Clone clones its internal option.Option slice by copy. Or if T implements Cloner[T], each element is cloned.

func (Elastic[T]) Equal

func (e Elastic[T]) Equal(other Elastic[T]) bool

Equal implements option.Equality[Elastic[T]].

Equal panics if T is uncomparable.

func (Elastic[T]) EqualFunc

func (e Elastic[T]) EqualFunc(other Elastic[T], cmp func(i, j T) bool) bool

EqualFunc reports whether two Elastic values are equal. EqualFunc checks state of both. If both state does not match, it returns false. If both are "defined" and lengths of their internal value match, it then checks equality of their value by cmp. It returns true if they are equal.

func (Elastic[T]) HasNull

func (e Elastic[T]) HasNull() bool

HasNull reports e is defined value has null in ins value.

func (Elastic[T]) IsDefined

func (e Elastic[T]) IsDefined() bool

IsDefined returns true if e is a defined Elastic[T], which includes a slice with no element.

func (Elastic[T]) IsNull

func (e Elastic[T]) IsNull() bool

IsNull returns true if e is a null Elastic[T].

func (Elastic[T]) IsUndefined

func (e Elastic[T]) IsUndefined() bool

IsUndefined returns true if e is an undefined Elastic[T].

func (Elastic[T]) IsZero

func (e Elastic[T]) IsZero() bool

IsZero is an alias for IsUndefined.

func (Elastic[T]) Iter

func (e Elastic[T]) Iter() iter.Seq[option.Option[option.Options[T]]]

Iter returns an iterator over the internal option. If e is undefined, the iterator yields nothing, otherwise the internal option.

func (Elastic[T]) Len

func (e Elastic[T]) Len() int

Len returns length of values.

func (Elastic[T]) LogValue

func (e Elastic[T]) LogValue() slog.Value

LogValue implements slog.LogValuer.

func (Elastic[T]) Map

func (e Elastic[T]) Map(f func(und.Und[option.Options[T]]) und.Und[option.Options[T]]) Elastic[T]

Map returns a new Elastic[T] whose internal value is e's mapped by f.

The internal slice of e is capped to its length before passed to f.

func (Elastic[T]) MarshalJSON

func (u Elastic[T]) MarshalJSON() ([]byte, error)

MarshalJSON implements json.Marshaler.

func (Elastic[T]) MarshalJSONV2

func (e Elastic[T]) MarshalJSONV2(enc *jsontext.Encoder, opts jsonv2.Options) error

MarshalJSONV2 implements jsonv2.MarshalerV2.

func (Elastic[T]) MarshalXML

func (e Elastic[T]) MarshalXML(enc *xml.Encoder, start xml.StartElement) error

MarshalXML implements xml.Marshaler.

func (Elastic[T]) PlainMultiple

func (e Elastic[T]) PlainMultiple() []*T

Deprecated: use Pointers

func (Elastic[T]) PlainSingle

func (e Elastic[T]) PlainSingle() *T

Deprecated: use Pointer.

func (Elastic[T]) Pointer

func (e Elastic[T]) Pointer() *T

Pointer returns a first value of its internal option slice as *T if e is defined.

Pointer returns nil if

• e is not defined
• e has no element
• e's first element is None.

func (Elastic[T]) Pointers

func (e Elastic[T]) Pointers() []*T

Pointer returns its internal option slice as []*T if e is defined.

func (Elastic[T]) UndCheck

func (e Elastic[T]) UndCheck() error

func (Elastic[T]) UndValidate

func (e Elastic[T]) UndValidate() error

func (*Elastic[T]) UnmarshalJSON

func (e *Elastic[T]) UnmarshalJSON(data []byte) error

UnmarshalJSON implements json.Unmarshaler.

func (*Elastic[T]) UnmarshalXML

func (e *Elastic[T]) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error

UnmarshalXML implements xml.Unmarshaler.

func (Elastic[T]) Unwrap

func (e Elastic[T]) Unwrap() und.Und[option.Options[T]]

Unwrap unwraps e.

func (Elastic[T]) Value

func (e Elastic[T]) Value() T

Value returns a first value of its internal option slice if e is defined. Otherwise it returns zero value for T.

func (Elastic[T]) ValueMultiple

func (e Elastic[T]) ValueMultiple() []T

Deprecated: use Values.

func (Elastic[T]) ValueSingle

func (e Elastic[T]) ValueSingle() T

Deprecated: use Value.

func (Elastic[T]) Values

func (e Elastic[T]) Values() []T

Values returns internal option slice as plain []T.

If e is not defined, it returns nil. Any None value in its internal option slice will be converted to zero value of T.