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optional

package module

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Versions in this module

v0

v0.12.0

Jun 5, 2024

v0.11.0

Jul 22, 2023

Changes in this version

+ var ErrSQLDriverValuerIncompatibleDataType = errors.New("incompatible data type for SQL driver Valuer on Option[T]")

+ var ErrSQLScannerIncompatibleDataType = errors.New("incompatible data type for SQL scanner on Option[T]")

type Option

+ func (o *Option[T]) Scan(src any) error

+ func (o Option[T]) UnwrapAsPtr() *T

+ func (o Option[T]) Value() (driver.Value, error)

v0.10.0

Dec 8, 2022

Changes in this version

type Option

+ func (o Option[T]) Or(fallbackOptionValue Option[T]) Option[T]

v0.9.0

Dec 7, 2022

Changes in this version

type Option

+ func (o Option[T]) OrElse(fallbackOptionValue Option[T]) Option[T]

v0.8.0

Nov 16, 2022

Changes in this version

type Option

+ func (o Option[T]) String() string

v0.7.0

Nov 12, 2022

Changes in this version

type Option

+ func FromNillable(v *T) Option[T]

+ func PtrFromNillable(v *T) Option[*T]

v0.6.0

Nov 9, 2022

v0.5.0

Sep 5, 2022

Changes in this version

type Option

+ func (o *Option[T]) UnmarshalJSON(data []byte) error

+ func (o Option[T]) MarshalJSON() ([]byte, error)

v0.4.0

Jun 13, 2022

Changes in this version

+ func FlatMapOr(option Option[T], fallbackValue U, mapper func(v T) Option[U]) U

+ func FlatMapOrWithError(option Option[T], fallbackValue U, mapper func(v T) (Option[U], error)) (U, error)

type Option

+ func FlatMap(option Option[T], mapper func(v T) Option[U]) Option[U]

+ func FlatMapWithError(option Option[T], mapper func(v T) (Option[U], error)) (Option[U], error)

v0.3.0

Jun 11, 2022

Changes in this version

type Option

+ func (o Option[T]) Unwrap() T

v0.2.0

Jun 10, 2022

Changes in this version

type Option

+ func (o Option[T]) IfNone(f func())

+ func (o Option[T]) IfNoneWithError(f func() error) error

+ func (o Option[T]) IfSome(f func(v T))

+ func (o Option[T]) IfSomeWithError(f func(v T) error) error

v0.1.0

May 27, 2022

Changes in this version

+ func MapOrWithError(option Option[T], fallbackValue U, mapper func(v T) (U, error)) (U, error)

type Option

+ func MapWithError(option Option[T], mapper func(v T) (U, error)) (Option[U], error)

v0.0.1

May 27, 2022

Changes in this version

+ var ErrNoneValueTaken = errors.New("none value taken")

+ func MapOr(option Option[T], fallbackValue U, mapper func(v T) U) U

+ func Unzip(zipped Option[Pair[T, U]]) (Option[T], Option[U])

+ func UnzipWith(zipped Option[V], unzipper func(zipped V) (T, U)) (Option[T], Option[U])

+ type Option struct

+ func Map(option Option[T], mapper func(v T) U) Option[U]

+ func None() Option[T]

+ func Some(value T) Option[T]

+ func Zip(opt1 Option[T], opt2 Option[U]) Option[Pair[T, U]]

+ func ZipWith(opt1 Option[T], opt2 Option[U], zipper func(opt1 T, opt2 U) V) Option[V]

+ func (o Option[T]) Filter(predicate func(v T) bool) Option[T]

+ func (o Option[T]) IsNone() bool

+ func (o Option[T]) IsSome() bool

+ func (o Option[T]) Take() (T, error)

+ func (o Option[T]) TakeOr(fallbackValue T) T

+ func (o Option[T]) TakeOrElse(fallbackFunc func() T) T

+ type Pair struct

+ Value1 T

+ Value2 U