mapz

Documentation

Index

• func DeleteWithLock[K comparable, V any](l sync.Locker, m map[K]V, key K)
• func KeysSorted[M ~map[K]V, K constraints.Ordered, V any](m M) []K
• func MaxKey[M ~map[K]V, K constraints.Ordered, V any](m M) K
• func MinKey[M ~map[K]V, K constraints.Ordered, V any](m M) K
• func MutexMapCompareAndDelete[K, V comparable](m *MutexMap[K, V], key K, old V) (deleted bool)
• func MutexMapCompareAndSwap[K, V comparable](m *MutexMap[K, V], key K, old, new V) bool
• func StoreWithLock[K comparable, V any](l sync.Locker, m map[K]V, key K, value V)
• func UnsyncedMapCompareAndDelete[K, V comparable](m *UnsyncedMap[K, V], key K, old V) (deleted bool)
• func UnsyncedMapCompareAndSwap[K, V comparable](m *UnsyncedMap[K, V], key K, old, new V) bool
• func ValuesSorted[M ~map[K]V, K comparable, V constraints.Ordered](m M) []V
• func ValuesSortedByKey[M ~map[K]V, K constraints.Ordered, V any](m M) []V
• type AppendMap
  • func (m *AppendMap[K, V]) Len() int
  • func (m *AppendMap[K, V]) Load(key K) (V, bool)
  • func (m *AppendMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool)
  • func (m *AppendMap[K, V]) LoadOrZero(key K) V
  • func (m *AppendMap[K, V]) Range(f func(key K, value V) bool)
  • func (m *AppendMap[K, V]) Snapshot() map[K]V
• type MutexMap
  • func (m *MutexMap[K, V]) Delete(key K)
  • func (m *MutexMap[K, V]) Len() int
  • func (m *MutexMap[K, V]) Load(key K) (V, bool)
  • func (m *MutexMap[K, V]) LoadAndDelete(key K) (V, bool)
  • func (m *MutexMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool)
  • func (m *MutexMap[K, V]) LoadOrZero(key K) V
  • func (m *MutexMap[K, V]) Range(f func(key K, value V) bool)
  • func (m *MutexMap[K, V]) Store(key K, value V)
  • func (m *MutexMap[K, V]) Swap(key K, value V) (previous V, loaded bool)
  • func (m *MutexMap[K, V]) WithLock(f func(m map[K]V))
• type SyncMap
  • func (m *SyncMap[K, V]) CompareAndDelete(key K, old V) (deleted bool)
  • func (m *SyncMap[K, V]) CompareAndSwap(key K, old, new V) bool
  • func (m *SyncMap[K, V]) Delete(key K)
  • func (m *SyncMap[K, V]) Load(key K) (V, bool)
  • func (m *SyncMap[K, V]) LoadAndDelete(key K) (V, bool)
  • func (m *SyncMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool)
  • func (m *SyncMap[K, V]) LoadOrZero(key K) V
  • func (m *SyncMap[K, V]) Range(f func(key K, value V) bool)
  • func (m *SyncMap[K, V]) Store(key K, value V)
  • func (m *SyncMap[K, V]) Swap(key K, value V) (previous V, loaded bool)
• type UnsyncedMap
  • func (m *UnsyncedMap[K, V]) Delete(key K)
  • func (m *UnsyncedMap[K, V]) Len() int
  • func (m *UnsyncedMap[K, V]) Load(key K) (V, bool)
  • func (m *UnsyncedMap[K, V]) LoadAndDelete(key K) (V, bool)
  • func (m *UnsyncedMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool)
  • func (m *UnsyncedMap[K, V]) LoadOrZero(key K) V
  • func (m *UnsyncedMap[K, V]) Range(f func(key K, value V) bool)
  • func (m *UnsyncedMap[K, V]) Store(key K, value V)
  • func (m *UnsyncedMap[K, V]) Swap(key K, value V) (previous V, loaded bool)
  • func (m *UnsyncedMap[K, V]) WithLock(f func(m map[K]V))

Functions

func DeleteWithLock

func DeleteWithLock[K comparable, V any](l sync.Locker, m map[K]V, key K)

DeleteWithLock grabs l and then calls delete(m, key). Useful one-liner for in a defer.

func KeysSorted

func KeysSorted[M ~map[K]V, K constraints.Ordered, V any](m M) []K

KeysSorted gets the keys of the given map, sorts them and returns them. KeysSorted may fail to sort correctly when sorting slices of floating-point numbers containing Not-a-number (NaN) values.

func MaxKey

func MaxKey[M ~map[K]V, K constraints.Ordered, V any](m M) K

MaxKey returns the highest key of the map m. It panics when m is empty.

func MinKey

func MinKey[M ~map[K]V, K constraints.Ordered, V any](m M) K

MinKey returns the lowest key of the map m. It panics when m is empty.

func MutexMapCompareAndDelete

func MutexMapCompareAndDelete[K, V comparable](m *MutexMap[K, V], key K, old V) (deleted bool)

CompareAndDelete deletes the entry for key if its value is equal to old.

If there is no current value for key in the map, CompareAndDelete returns false.

This is a function rather than a method because Go 1.18 doesn't allow restricting a method's type parameters more than the base type (yet?).

func MutexMapCompareAndSwap

func MutexMapCompareAndSwap[K, V comparable](m *MutexMap[K, V], key K, old, new V) bool

CompareAndSwap swaps the old and new values for key if the value stored in the map is equal to old. The old value must be of a comparable type.

This is a function rather than a method because Go 1.18 doesn't allow restricting a method's type parameters more than the base type (yet?).

func StoreWithLock

func StoreWithLock[K comparable, V any](l sync.Locker, m map[K]V, key K, value V)

StoreWithLock grabs l and then does m[key] = value. Useful one-liner for in a defer.

func UnsyncedMapCompareAndDelete

func UnsyncedMapCompareAndDelete[K, V comparable](m *UnsyncedMap[K, V], key K, old V) (deleted bool)

CompareAndDelete deletes the entry for key if its value is equal to old.

If there is no current value for key in the map, CompareAndDelete returns false.

This is a function rather than a method because Go 1.18 doesn't allow restricting a method's type parameters more than the base type (yet?).

func UnsyncedMapCompareAndSwap

func UnsyncedMapCompareAndSwap[K, V comparable](m *UnsyncedMap[K, V], key K, old, new V) bool

CompareAndSwap swaps the old and new values for key if the value stored in the map is equal to old. The old value must be of a comparable type.

This is a function rather than a method because Go 1.18 doesn't allow restricting a method's type parameters more than the base type (yet?).

func ValuesSorted

func ValuesSorted[M ~map[K]V, K comparable, V constraints.Ordered](m M) []V

ValuesSorted gets the values of the given map, sorts them and returns them. ValuesSorted may fail to sort correctly when sorting slices of floating-point numbers containing Not-a-number (NaN) values.

func ValuesSortedByKey

func ValuesSortedByKey[M ~map[K]V, K constraints.Ordered, V any](m M) []V

ValuesSortedByKey gets the values of the given map, sorts them by their key and returns them. ValuesSortedByKey may fail to sort correctly when sorting slices of floating-point numbers containing Not-a-number (NaN) values.

Types

type AppendMap

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

AppendMap is a concurrency-safe append-only map. Its interface resembles a subset of sync.Map. Loads on existing values only need an atomic read. Loads of non-existent and recently stored values pick up a mutex. Stores pick up a mutex. The zero value is valid.

func (*AppendMap[K, V]) Len

func (m *AppendMap[K, V]) Len() int

Len returns the number of elements in the map.

func (*AppendMap[K, V]) Load

func (m *AppendMap[K, V]) Load(key K) (V, bool)

Load returns the value stored in the map for a key. The ok result indicates whether value was found in the map.

func (*AppendMap[K, V]) LoadOrStore

func (m *AppendMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool)

LoadOrStore returns the existing value for the key if present. Otherwise, it stores and returns the given value. The loaded result is true if the value was loaded, false if stored.

func (*AppendMap[K, V]) LoadOrZero

func (m *AppendMap[K, V]) LoadOrZero(key K) V

LoadOrZero returns the value stored in the map for a key, or zero if no value is present. This is the same as Load() but ignoring the second result.

func (*AppendMap[K, V]) Range

func (m *AppendMap[K, V]) Range(f func(key K, value V) bool)

Range calls f sequentially for each key and value present in the map. If f returns false, range stops the iteration.

Range does not block other methods on the receiver; even f itself may call any method on m.

Range iterates over a consistent copy of the map, snapshotted before the first callback.

func (*AppendMap[K, V]) Snapshot

func (m *AppendMap[K, V]) Snapshot() map[K]V

Snapshot returns a read-only map[K]V. Any writes that have happened before are reflected. It should not be modified if the AppendMap could be used in the future. Future calls to the AppendMap will not modify the returned map.

type MutexMap

type MutexMap[K comparable, V any] struct {
	L sync.Mutex
	M map[K]V
}

MutexMap is a map protected with a mutex. Its interface closely resembles sync.Map. The zero value is valid.

func (*MutexMap[K, V]) Delete

func (m *MutexMap[K, V]) Delete(key K)

Delete deletes the value for a key.

func (*MutexMap[K, V]) Len

func (m *MutexMap[K, V]) Len() int

Len returns the number of elements in the map.

func (*MutexMap[K, V]) Load

func (m *MutexMap[K, V]) Load(key K) (V, bool)

Load returns the value stored in the map for a key. The ok result indicates whether value was found in the map.

func (*MutexMap[K, V]) LoadAndDelete

func (m *MutexMap[K, V]) LoadAndDelete(key K) (V, bool)

LoadAndDelete deletes the value for a key, returning the previous value if any. The second result reports whether the key was present.

func (*MutexMap[K, V]) LoadOrStore

func (m *MutexMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool)

LoadOrStore returns the existing value for the key if present. Otherwise, it stores and returns the given value. The loaded result is true if the value was loaded, false if stored.

func (*MutexMap[K, V]) LoadOrZero

func (m *MutexMap[K, V]) LoadOrZero(key K) V

LoadOrZero returns the value stored in the map for a key, or zero if no value is present. This is the same as Load() but ignoring the second result.

func (*MutexMap[K, V]) Range

func (m *MutexMap[K, V]) Range(f func(key K, value V) bool)

Range calls f sequentially for each key and value present in the map. If f returns false, range stops the iteration.

Range does not block other methods on the receiver; even f itself may call any method on m.

Range repeatedly picks up and drops the mutex so f() won't be called with the mutex held. Use WithLock if you need more performance at the cost of blocking other users.

func (*MutexMap[K, V]) Store

func (m *MutexMap[K, V]) Store(key K, value V)

Store sets the value for a key.

func (*MutexMap[K, V]) Swap

func (m *MutexMap[K, V]) Swap(key K, value V) (previous V, loaded bool)

Swap swaps the value for a key and returns the previous value if any. The loaded result reports whether the key was present.

func (*MutexMap[K, V]) WithLock

func (m *MutexMap[K, V]) WithLock(f func(m map[K]V))

WithLock calls f while holding the lock. f can manipulate the given map at will, but can't use m's regular functions because it's already holding the lock itself.

type SyncMap

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

func (*SyncMap[K, V]) CompareAndDelete

func (m *SyncMap[K, V]) CompareAndDelete(key K, old V) (deleted bool)

CompareAndDelete deletes the entry for key if its value is equal to old. The old value must be of a comparable type.

If there is no current value for key in the map, CompareAndDelete returns false (even if the old value is the nil interface value).

CompareAndDelete is only available from Go 1.20 as that is when Go added the sync.Map.CompareAndDelete method.

func (*SyncMap[K, V]) CompareAndSwap

func (m *SyncMap[K, V]) CompareAndSwap(key K, old, new V) bool

CompareAndSwap swaps the old and new values for key if the value stored in the map is equal to old. The old value must be of a comparable type.

CompareAndSwap is only available from Go 1.20 as that is when Go added the sync.Map.CompareAndSwap method.

func (*SyncMap[K, V]) Delete

func (m *SyncMap[K, V]) Delete(key K)

Delete deletes the value for a key.

func (*SyncMap[K, V]) Load

func (m *SyncMap[K, V]) Load(key K) (V, bool)

Load returns the value stored in the map for a key. The ok result indicates whether value was found in the map.

func (*SyncMap[K, V]) LoadAndDelete

func (m *SyncMap[K, V]) LoadAndDelete(key K) (V, bool)

LoadAndDelete deletes the value for a key, returning the previous value if any. The second result reports whether the key was present.

func (*SyncMap[K, V]) LoadOrStore

func (m *SyncMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool)

LoadOrStore returns the existing value for the key if present. Otherwise, it stores and returns the given value. The loaded result is true if the value was loaded, false if stored.

func (*SyncMap[K, V]) LoadOrZero

func (m *SyncMap[K, V]) LoadOrZero(key K) V

Load returns the value stored in the map for a key, or zero if no value is present. This is the same as Load() but ignoring the second result.

func (*SyncMap[K, V]) Range

func (m *SyncMap[K, V]) Range(f func(key K, value V) bool)

Range calls f sequentially for each key and value present in the map. If f returns false, range stops the iteration.

Range does not necessarily correspond to any consistent snapshot of the Map's contents: no key will be visited more than once, but if the value for any key is stored or deleted concurrently (including by f), Range may reflect any mapping for that key from any point during the Range call. Range does not block other methods on the receiver; even f itself may call any method on m.

Range may be O(N) with the number of elements in the map even if f returns false after a constant number of calls.

func (*SyncMap[K, V]) Store

func (m *SyncMap[K, V]) Store(key K, value V)

Store sets the value for a key.

func (*SyncMap[K, V]) Swap

func (m *SyncMap[K, V]) Swap(key K, value V) (previous V, loaded bool)

Swap swaps the value for a key and returns the previous value if any. The loaded result reports whether the key was present.

Swap is only available from Go 1.20 as that is when Go added the sync.Map.Swap method.

type UnsyncedMap

type UnsyncedMap[K comparable, V any] struct {
	M map[K]V
}

UnsyncedMap is a map protected with a mutex. Its interface closely resembles sync.Map. It's indended as a drop-in replacement for MutexMap and SyncMap when synchronization is no longer needed (but might become so in the future). The zero value is valid.

func (*UnsyncedMap[K, V]) Delete

func (m *UnsyncedMap[K, V]) Delete(key K)

Delete deletes the value for a key.

func (*UnsyncedMap[K, V]) Len

func (m *UnsyncedMap[K, V]) Len() int

Len returns the number of elements in the map.

func (*UnsyncedMap[K, V]) Load

func (m *UnsyncedMap[K, V]) Load(key K) (V, bool)

Load returns the value stored in the map for a key. The ok result indicates whether value was found in the map.

func (*UnsyncedMap[K, V]) LoadAndDelete

func (m *UnsyncedMap[K, V]) LoadAndDelete(key K) (V, bool)

LoadAndDelete deletes the value for a key, returning the previous value if any. The second result reports whether the key was present.

func (*UnsyncedMap[K, V]) LoadOrStore

func (m *UnsyncedMap[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool)

LoadOrStore returns the existing value for the key if present. Otherwise, it stores and returns the given value. The loaded result is true if the value was loaded, false if stored.

func (*UnsyncedMap[K, V]) LoadOrZero

func (m *UnsyncedMap[K, V]) LoadOrZero(key K) V

Load returns the value stored in the map for a key, or zero if no value is present. This is the same as Load() but ignoring the second result.

func (*UnsyncedMap[K, V]) Range

func (m *UnsyncedMap[K, V]) Range(f func(key K, value V) bool)

Range calls f sequentially for each key and value present in the map. If f returns false, range stops the iteration.

func (*UnsyncedMap[K, V]) Store

func (m *UnsyncedMap[K, V]) Store(key K, value V)

Store sets the value for a key.

func (*UnsyncedMap[K, V]) Swap

func (m *UnsyncedMap[K, V]) Swap(key K, value V) (previous V, loaded bool)

Swap swaps the value for a key and returns the previous value if any. The loaded result reports whether the key was present.

func (*UnsyncedMap[K, V]) WithLock

func (m *UnsyncedMap[K, V]) WithLock(f func(m map[K]V))

WithLock calls f. The name is based on the MutexMap method, but UnsyncedMap has no mutex.