views

Documentation

Overview

Package views provides read-only accessors for commonly used value types.

Index

• func AppendStrings[T fmt.Stringer](dst []string, v Slice[T]) []string
• func ContainsPointers[T any]() bool
• func SliceContains[T comparable](v Slice[T], e T) bool
• func SliceEqual[T comparable](a, b Slice[T]) bool
• func SliceEqualAnyOrder[T comparable](a, b Slice[T]) bool
• type ByteSlice
  • func ByteSliceOf[T ~[]byte](x T) ByteSlice[T]
  • func (v ByteSlice[T]) AppendTo(dst T) T
  • func (v ByteSlice[T]) AsSlice() T
  • func (v ByteSlice[T]) At(i int) byte
  • func (v ByteSlice[T]) Equal(b T) bool
  • func (v ByteSlice[T]) EqualView(b ByteSlice[T]) bool
  • func (v ByteSlice[T]) IsNil() bool
  • func (v ByteSlice[T]) Len() int
  • func (v ByteSlice[T]) MapKey() SliceMapKey[byte]
  • func (v ByteSlice[T]) MarshalJSON() ([]byte, error)
  • func (v ByteSlice[T]) Mem() mem.RO
  • func (v ByteSlice[T]) Slice(i, j int) ByteSlice[T]
  • func (v ByteSlice[T]) SliceFrom(i int) ByteSlice[T]
  • func (v ByteSlice[T]) SliceTo(i int) ByteSlice[T]
  • func (v *ByteSlice[T]) UnmarshalJSON(b []byte) error
• type Cloner
• type Map
  • func MapOf[K comparable, V any](m map[K]V) Map[K, V]
  • func (m Map[K, V]) AsMap() map[K]V
  • func (m Map[K, V]) Contains(k K) bool
  • func (m Map[K, V]) Get(k K) V
  • func (m Map[K, V]) GetOk(k K) (V, bool)
  • func (m Map[K, V]) Has(k K) bool
  • func (m Map[K, V]) IsNil() bool
  • func (m Map[K, V]) Len() int
  • func (m Map[K, V]) MarshalJSON() ([]byte, error)
  • func (m Map[K, V]) Range(f MapRangeFn[K, V])
  • func (m *Map[K, V]) UnmarshalJSON(b []byte) error
• type MapFn
  • func MapFnOf[K comparable, T any, V any](m map[K]T, f func(T) V) MapFn[K, T, V]
  • func (m MapFn[K, T, V]) Contains(k K) bool
  • func (m MapFn[K, T, V]) Get(k K) V
  • func (m MapFn[K, T, V]) GetOk(k K) (V, bool)
  • func (m MapFn[K, T, V]) Has(k K) bool
  • func (m MapFn[K, T, V]) IsNil() bool
  • func (m MapFn[K, T, V]) Len() int
  • func (m MapFn[K, T, V]) Range(f MapRangeFn[K, V])
• type MapRangeFn
• type MapSlice
  • func MapSliceOf[K comparable, V any](m map[K][]V) MapSlice[K, V]
  • func (m MapSlice[K, V]) AsMap() map[K][]V
  • func (m MapSlice[K, V]) Contains(k K) bool
  • func (m MapSlice[K, V]) Get(k K) Slice[V]
  • func (m MapSlice[K, V]) GetOk(k K) (Slice[V], bool)
  • func (m MapSlice[K, V]) IsNil() bool
  • func (m MapSlice[K, V]) Len() int
  • func (m MapSlice[K, V]) MarshalJSON() ([]byte, error)
  • func (m MapSlice[K, V]) Range(f MapRangeFn[K, Slice[V]])
  • func (m *MapSlice[K, V]) UnmarshalJSON(b []byte) error
• type Slice
  • func SliceOf[T any](x []T) Slice[T]
  • func (v Slice[T]) AppendTo(dst []T) []T
  • func (v Slice[T]) AsSlice() []T
  • func (v Slice[T]) At(i int) T
  • func (v Slice[T]) ContainsFunc(f func(T) bool) bool
  • func (v Slice[T]) IndexFunc(f func(T) bool) int
  • func (v Slice[T]) IsNil() bool
  • func (v Slice[T]) Len() int
  • func (v Slice[T]) MapKey() SliceMapKey[T]
  • func (v Slice[T]) MarshalJSON() ([]byte, error)
  • func (v Slice[T]) Slice(i, j int) Slice[T]
  • func (v Slice[T]) SliceFrom(i int) Slice[T]
  • func (v Slice[T]) SliceTo(i int) Slice[T]
  • func (v *Slice[T]) UnmarshalJSON(b []byte) error
• type SliceMapKey
• type SliceView
  • func SliceOfViews[T ViewCloner[T, V], V StructView[T]](x []T) SliceView[T, V]
  • func (v SliceView[T, V]) AppendTo(dst []V) []V
  • func (v SliceView[T, V]) AsSlice() []V
  • func (v SliceView[T, V]) At(i int) V
  • func (v SliceView[T, V]) IsNil() bool
  • func (v SliceView[T, V]) Len() int
  • func (v SliceView[T, V]) MapKey() SliceMapKey[T]
  • func (v SliceView[T, V]) MarshalJSON() ([]byte, error)
  • func (v SliceView[T, V]) Slice(i, j int) SliceView[T, V]
  • func (v SliceView[T, V]) SliceFrom(i int) SliceView[T, V]
  • func (v SliceView[T, V]) SliceTo(i int) SliceView[T, V]
  • func (v *SliceView[T, V]) UnmarshalJSON(b []byte) error
• type StructView
• type ViewCloner

Functions

func AppendStrings

func AppendStrings[T fmt.Stringer](dst []string, v Slice[T]) []string

AppendStrings appends the string representation of each element in v to dst.

func ContainsPointers

func ContainsPointers[T any]() bool

ContainsPointers reports whether T contains any pointers, either explicitly or implicitly. It has special handling for some types that contain pointers that we know are free from memory aliasing/mutation concerns.

func SliceContains

func SliceContains[T comparable](v Slice[T], e T) bool

SliceContains reports whether v contains element e.

As it runs in O(n) time, use with care.

func SliceEqual

func SliceEqual[T comparable](a, b Slice[T]) bool

SliceEqual is like the standard library's slices.Equal, but for two views.

func SliceEqualAnyOrder

func SliceEqualAnyOrder[T comparable](a, b Slice[T]) bool

SliceEqualAnyOrder reports whether a and b contain the same elements, regardless of order. The underlying slices for a and b can be nil.

Types

type ByteSlice

type ByteSlice[T ~[]byte] struct {
	// contains filtered or unexported fields
}

ByteSlice is a read-only accessor for types that are backed by a []byte.

func ByteSliceOf

func ByteSliceOf[T ~[]byte](x T) ByteSlice[T]

ByteSliceOf returns a ByteSlice for the provided slice.

func (ByteSlice[T]) AppendTo

func (v ByteSlice[T]) AppendTo(dst T) T

AppendTo appends the underlying slice values to dst.

func (ByteSlice[T]) AsSlice

func (v ByteSlice[T]) AsSlice() T

AsSlice returns a copy of the underlying slice.

func (ByteSlice[T]) At

func (v ByteSlice[T]) At(i int) byte

At returns the byte at index `i` of the slice.

func (ByteSlice[T]) Equal

func (v ByteSlice[T]) Equal(b T) bool

Equal reports whether the underlying slice is equal to b.

func (ByteSlice[T]) EqualView

func (v ByteSlice[T]) EqualView(b ByteSlice[T]) bool

EqualView reports whether the underlying slice is equal to b.

func (ByteSlice[T]) IsNil

func (v ByteSlice[T]) IsNil() bool

IsNil reports whether the underlying slice is nil.

func (ByteSlice[T]) Len

func (v ByteSlice[T]) Len() int

Len returns the length of the slice.

func (ByteSlice[T]) MapKey

func (v ByteSlice[T]) MapKey() SliceMapKey[byte]

MapKey returns a unique key for a slice, based on its address and length.

func (ByteSlice[T]) MarshalJSON

func (v ByteSlice[T]) MarshalJSON() ([]byte, error)

MarshalJSON implements json.Marshaler.

func (ByteSlice[T]) Mem

func (v ByteSlice[T]) Mem() mem.RO

Mem returns a read-only view of the underlying slice.

func (ByteSlice[T]) Slice

func (v ByteSlice[T]) Slice(i, j int) ByteSlice[T]

Slice returns v[i:j]

func (ByteSlice[T]) SliceFrom

func (v ByteSlice[T]) SliceFrom(i int) ByteSlice[T]

SliceFrom returns v[i:].

func (ByteSlice[T]) SliceTo

func (v ByteSlice[T]) SliceTo(i int) ByteSlice[T]

SliceTo returns v[:i]

func (*ByteSlice[T]) UnmarshalJSON

func (v *ByteSlice[T]) UnmarshalJSON(b []byte) error

UnmarshalJSON implements json.Unmarshaler.

type Cloner

type Cloner[T any] interface {
	// Clone returns a deep-clone of the receiver.
	// It returns nil, when the receiver is nil.
	Clone() T
}

Cloner is any type that has a Clone function returning a deep-clone of the receiver.

type Map

type Map[K comparable, V any] struct {
	// contains filtered or unexported fields
}

Map provides a read-only view of a map. It is the caller's responsibility to make sure V is immutable.

func MapOf

func MapOf[K comparable, V any](m map[K]V) Map[K, V]

MapOf returns a view over m. It is the caller's responsibility to make sure V is immutable.

func (Map[K, V]) AsMap

func (m Map[K, V]) AsMap() map[K]V

AsMap returns a shallow-clone of the underlying map. If V is a pointer type, it is the caller's responsibility to make sure the values are immutable.

func (Map[K, V]) Contains

func (m Map[K, V]) Contains(k K) bool

Contains reports whether k has an entry in the map.

func (Map[K, V]) Get

func (m Map[K, V]) Get(k K) V

Get returns the element with key k.

func (Map[K, V]) GetOk

func (m Map[K, V]) GetOk(k K) (V, bool)

GetOk returns the element with key k and a bool representing whether the key is in map.

func (Map[K, V]) Has

func (m Map[K, V]) Has(k K) bool

Has reports whether k has an entry in the map. Deprecated: use Contains instead.

func (Map[K, V]) IsNil

func (m Map[K, V]) IsNil() bool

IsNil reports whether the underlying map is nil.

func (Map[K, V]) Len

func (m Map[K, V]) Len() int

Len returns the number of elements in the map.

func (Map[K, V]) MarshalJSON

func (m Map[K, V]) MarshalJSON() ([]byte, error)

MarshalJSON implements json.Marshaler.

func (Map[K, V]) Range

func (m Map[K, V]) Range(f MapRangeFn[K, V])

Range calls f for every k,v pair in the underlying map. It stops iteration immediately if f returns false.

func (*Map[K, V]) UnmarshalJSON

func (m *Map[K, V]) UnmarshalJSON(b []byte) error

UnmarshalJSON implements json.Unmarshaler. It should only be called on an uninitialized Map.

type MapFn

type MapFn[K comparable, T any, V any] struct {
	// contains filtered or unexported fields
}

MapFn is like Map but with a func to convert values from T to V. It is used to provide map of slices and views.

func MapFnOf

func MapFnOf[K comparable, T any, V any](m map[K]T, f func(T) V) MapFn[K, T, V]

MapFnOf returns a MapFn for m.

func (MapFn[K, T, V]) Contains

func (m MapFn[K, T, V]) Contains(k K) bool

Contains reports whether k has an entry in the map.

func (MapFn[K, T, V]) Get

func (m MapFn[K, T, V]) Get(k K) V

Get returns the element with key k.

func (MapFn[K, T, V]) GetOk

func (m MapFn[K, T, V]) GetOk(k K) (V, bool)

GetOk returns the element with key k and a bool representing whether the key is in map.

func (MapFn[K, T, V]) Has

func (m MapFn[K, T, V]) Has(k K) bool

Has reports whether k has an entry in the map. Deprecated: use Contains instead.

func (MapFn[K, T, V]) IsNil

func (m MapFn[K, T, V]) IsNil() bool

IsNil reports whether the underlying map is nil.

func (MapFn[K, T, V]) Len

func (m MapFn[K, T, V]) Len() int

Len returns the number of elements in the map.

func (MapFn[K, T, V]) Range

func (m MapFn[K, T, V]) Range(f MapRangeFn[K, V])

Range calls f for every k,v pair in the underlying map. It stops iteration immediately if f returns false.

type MapRangeFn

type MapRangeFn[K comparable, V any] func(k K, v V) (cont bool)

MapRangeFn is the func called from a Map.Range call. Implementations should return false to stop range.

type MapSlice

type MapSlice[K comparable, V any] struct {
	// contains filtered or unexported fields
}

MapSlice is a view over a map whose values are slices.

func MapSliceOf

func MapSliceOf[K comparable, V any](m map[K][]V) MapSlice[K, V]

MapSliceOf returns a MapSlice for the provided map. It is the caller's responsibility to make sure V is immutable.

func (MapSlice[K, V]) AsMap

func (m MapSlice[K, V]) AsMap() map[K][]V

AsMap returns a shallow-clone of the underlying map.

If V is a pointer type, it is the caller's responsibility to make sure the values are immutable. The map and slices are cloned, but the values are not.

func (MapSlice[K, V]) Contains

func (m MapSlice[K, V]) Contains(k K) bool

Contains reports whether k has an entry in the map.

func (MapSlice[K, V]) Get

func (m MapSlice[K, V]) Get(k K) Slice[V]

Get returns the element with key k.

func (MapSlice[K, V]) GetOk

func (m MapSlice[K, V]) GetOk(k K) (Slice[V], bool)

GetOk returns the element with key k and a bool representing whether the key is in map.

func (MapSlice[K, V]) IsNil

func (m MapSlice[K, V]) IsNil() bool

IsNil reports whether the underlying map is nil.

func (MapSlice[K, V]) Len

func (m MapSlice[K, V]) Len() int

Len returns the number of elements in the map.

func (MapSlice[K, V]) MarshalJSON

func (m MapSlice[K, V]) MarshalJSON() ([]byte, error)

MarshalJSON implements json.Marshaler.

func (MapSlice[K, V]) Range

func (m MapSlice[K, V]) Range(f MapRangeFn[K, Slice[V]])

Range calls f for every k,v pair in the underlying map. It stops iteration immediately if f returns false.

func (*MapSlice[K, V]) UnmarshalJSON

func (m *MapSlice[K, V]) UnmarshalJSON(b []byte) error

UnmarshalJSON implements json.Unmarshaler. It should only be called on an uninitialized Map.

type Slice

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

Slice is a read-only accessor for a slice.

func SliceOf

func SliceOf[T any](x []T) Slice[T]

SliceOf returns a Slice for the provided slice for immutable values. It is the caller's responsibility to make sure V is immutable.

func (Slice[T]) AppendTo

func (v Slice[T]) AppendTo(dst []T) []T

AppendTo appends the underlying slice values to dst.

func (Slice[T]) AsSlice

func (v Slice[T]) AsSlice() []T

AsSlice returns a copy of underlying slice.

func (Slice[T]) At

func (v Slice[T]) At(i int) T

At returns the element at index `i` of the slice.

func (Slice[T]) ContainsFunc

func (v Slice[T]) ContainsFunc(f func(T) bool) bool

ContainsFunc reports whether any element in v satisfies f(e).

As it runs in O(n) time, use with care.

func (Slice[T]) IndexFunc

func (v Slice[T]) IndexFunc(f func(T) bool) int

IndexFunc returns the first index of an element in v satisfying f(e), or -1 if none do.

As it runs in O(n) time, use with care.

func (Slice[T]) IsNil

func (v Slice[T]) IsNil() bool

IsNil reports whether the underlying slice is nil.

func (Slice[T]) Len

func (v Slice[T]) Len() int

Len returns the length of the slice.

func (Slice[T]) MapKey

func (v Slice[T]) MapKey() SliceMapKey[T]

MapKey returns a unique key for a slice, based on its address and length.

func (Slice[T]) MarshalJSON

func (v Slice[T]) MarshalJSON() ([]byte, error)

MarshalJSON implements json.Marshaler.

func (Slice[T]) Slice

func (v Slice[T]) Slice(i, j int) Slice[T]

Slice returns v[i:j]

func (Slice[T]) SliceFrom

func (v Slice[T]) SliceFrom(i int) Slice[T]

SliceFrom returns v[i:].

func (Slice[T]) SliceTo

func (v Slice[T]) SliceTo(i int) Slice[T]

SliceTo returns v[:i]

func (*Slice[T]) UnmarshalJSON

func (v *Slice[T]) UnmarshalJSON(b []byte) error

UnmarshalJSON implements json.Unmarshaler.

type SliceMapKey

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

SliceMapKey represents a comparable unique key for a slice, based on its address and length. It can be used to key maps by slices but should only be used when the underlying slice is immutable.

Empty and nil slices have different keys.

type SliceView

type SliceView[T ViewCloner[T, V], V StructView[T]] struct {
	// contains filtered or unexported fields
}

SliceView wraps []T to provide accessors which return an immutable view V of T. It is used to provide the equivalent of SliceOf([]V) without having to allocate []V from []T.

func SliceOfViews

func SliceOfViews[T ViewCloner[T, V], V StructView[T]](x []T) SliceView[T, V]

SliceOfViews returns a ViewSlice for x.

func (SliceView[T, V]) AppendTo

func (v SliceView[T, V]) AppendTo(dst []V) []V

AppendTo appends the underlying slice values to dst.

func (SliceView[T, V]) AsSlice

func (v SliceView[T, V]) AsSlice() []V

AsSlice returns a copy of underlying slice.

func (SliceView[T, V]) At

func (v SliceView[T, V]) At(i int) V

At returns a View of the element at index `i` of the slice.

func (SliceView[T, V]) IsNil

func (v SliceView[T, V]) IsNil() bool

IsNil reports whether the underlying slice is nil.

func (SliceView[T, V]) Len

func (v SliceView[T, V]) Len() int

Len returns the length of the slice.

func (SliceView[T, V]) MapKey

func (v SliceView[T, V]) MapKey() SliceMapKey[T]

MapKey returns a unique key for a slice, based on its address and length.

func (SliceView[T, V]) MarshalJSON

func (v SliceView[T, V]) MarshalJSON() ([]byte, error)

MarshalJSON implements json.Marshaler.

func (SliceView[T, V]) Slice

func (v SliceView[T, V]) Slice(i, j int) SliceView[T, V]

Slice returns v[i:j]

func (SliceView[T, V]) SliceFrom

func (v SliceView[T, V]) SliceFrom(i int) SliceView[T, V]

SliceFrom returns v[i:].

func (SliceView[T, V]) SliceTo

func (v SliceView[T, V]) SliceTo(i int) SliceView[T, V]

SliceTo returns v[:i]

func (*SliceView[T, V]) UnmarshalJSON

func (v *SliceView[T, V]) UnmarshalJSON(b []byte) error

UnmarshalJSON implements json.Unmarshaler.

type StructView

type StructView[T any] interface {
	// Valid reports whether the underlying Viewable is nil.
	Valid() bool
	// AsStruct returns a deep-copy of the underlying value.
	// It returns nil, if Valid() is false.
	AsStruct() T
}

StructView represents the corresponding StructView of a Viewable. The concrete types are typically generated by tailscale.com/cmd/viewer.

type ViewCloner

type ViewCloner[T any, V StructView[T]] interface {
	// View returns a read-only view of Viewable.
	// If Viewable is nil, View().Valid() reports false.
	View() V
	// Clone returns a deep-clone of Viewable.
	// It returns nil, when Viewable is nil.
	Clone() T
}

ViewCloner is any type that has had View and Clone funcs generated using tailscale.com/cmd/viewer.