opt

Documentation

Overview

Package opt defines optional types.

Index

• type Bool
  • func NewBool(b bool) Bool
  • func (b *Bool) Clear()
  • func (b Bool) EqualBool(v bool) bool
  • func (b Bool) Get() (v bool, ok bool)
  • func (b Bool) MarshalJSON() ([]byte, error)
  • func (b *Bool) Scan(src any) error
  • func (b *Bool) Set(v bool)
  • func (b *Bool) UnmarshalJSON(j []byte) error
• type BoolFlag
  • func (b *BoolFlag) Set(s string) error
  • func (b *BoolFlag) String() string
• type Value
  • func ValueOf[T any](v T) Value[T]
  • func (o *Value[T]) Clear()
  • func (o Value[T]) Equal(v Value[T]) bool
  • func (o Value[T]) Get() T
  • func (o Value[T]) GetOk() (v T, ok bool)
  • func (o Value[T]) GetOr(def T) T
  • func (o *Value[T]) IsSet() bool
  • func (o Value[T]) MarshalJSON() ([]byte, error)
  • func (o Value[T]) MarshalJSONV2(enc *jsontext.Encoder, opts jsonv2.Options) error
  • func (o *Value[T]) Set(v T)
  • func (o Value[T]) String() string
  • func (o *Value[T]) UnmarshalJSON(b []byte) error
  • func (o *Value[T]) UnmarshalJSONV2(dec *jsontext.Decoder, opts jsonv2.Options) error

Types

type Bool

type Bool string

Bool represents an optional boolean to be JSON-encoded. The string is either "true", "false", or the empty string to mean unset.

As a special case, the underlying string may also be the string "unset" as as a synonym for the empty string. This lets the explicit unset value be exchanged over an encoding/json "omitempty" field without it being dropped.

func NewBool

func NewBool(b bool) Bool

NewBool constructs a new Bool value equal to b. The returned Bool is set, unless Set("") or Clear() methods are called.

func (*Bool) Clear

func (b *Bool) Clear()

func (Bool) EqualBool

func (b Bool) EqualBool(v bool) bool

EqualBool reports whether b is equal to v. If b is empty or not a valid bool, it reports false.

func (Bool) Get

func (b Bool) Get() (v bool, ok bool)

func (Bool) MarshalJSON

func (b Bool) MarshalJSON() ([]byte, error)

func (*Bool) Scan

func (b *Bool) Scan(src any) error

Scan implements database/sql.Scanner.

func (*Bool) Set

func (b *Bool) Set(v bool)

func (*Bool) UnmarshalJSON

func (b *Bool) UnmarshalJSON(j []byte) error

type BoolFlag

type BoolFlag struct {
	*Bool
}

BoolFlag is a wrapper for Bool that implements flag.Value.

func (*BoolFlag) Set

func (b *BoolFlag) Set(s string) error

Set the value of b, using any value supported by strconv.ParseBool.

func (*BoolFlag) String

func (b *BoolFlag) String() string

String returns "true" or "false" if the value is set, or an empty string otherwise.

type Value

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

Value is an optional value to be JSON-encoded. With encoding/json, a zero Value is marshaled as a JSON null. With github.com/go-json-experiment/json, a zero Value is omitted from the JSON object if the Go struct field specified with omitzero. The omitempty tag option should never be used with Value fields.

func ValueOf

func ValueOf[T any](v T) Value[T]

ValueOf returns an optional Value containing the specified value. It treats nil slices and maps as empty slices and maps.

func (*Value[T]) Clear

func (o *Value[T]) Clear()

Clear resets o to an empty state.

func (Value[T]) Equal

func (o Value[T]) Equal(v Value[T]) bool

Equal reports whether o is equal to v. Two optional values are equal if both are empty, or if both are set and the underlying values are equal. If the template type T implements an Equal(T) bool method, it will be used instead of the == operator for value comparison. If T is not comparable, it returns false.

func (Value[T]) Get

func (o Value[T]) Get() T

Get returns the value of o. If a value hasn't been set, a zero value of T will be returned.

func (Value[T]) GetOk

func (o Value[T]) GetOk() (v T, ok bool)

Get returns the value and a flag indicating whether the value is set.

func (Value[T]) GetOr

func (o Value[T]) GetOr(def T) T

GetOr returns the value of o or def if a value hasn't been set.

func (*Value[T]) IsSet

func (o *Value[T]) IsSet() bool

IsSet reports whether o has a value set.

func (Value[T]) MarshalJSON

func (o Value[T]) MarshalJSON() ([]byte, error)

MarshalJSON implements [json.Marshaler].

func (Value[T]) MarshalJSONV2

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

MarshalJSONV2 implements jsonv2.MarshalerV2.

func (*Value[T]) Set

func (o *Value[T]) Set(v T)

Set assigns the specified value to the optional value o.

func (Value[T]) String

func (o Value[T]) String() string

String implements fmt.Stringer.

func (*Value[T]) UnmarshalJSON

func (o *Value[T]) UnmarshalJSON(b []byte) error

UnmarshalJSON implements [json.Unmarshaler].

func (*Value[T]) UnmarshalJSONV2

func (o *Value[T]) UnmarshalJSONV2(dec *jsontext.Decoder, opts jsonv2.Options) error

UnmarshalJSONV2 implements jsonv2.UnmarshalerV2.