Documentation
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Index ¶
- Variables
- type Item
- type PrefixQueue
- func (pq *PrefixQueue) Close() error
- func (pq *PrefixQueue) Dequeue(prefix []byte) (*Item, error)
- func (pq *PrefixQueue) DequeueString(prefix string) (*Item, error)
- func (pq *PrefixQueue) Enqueue(prefix, value []byte) (*Item, error)
- func (pq *PrefixQueue) EnqueueObject(prefix []byte, value interface{}) (*Item, error)
- func (pq *PrefixQueue) EnqueueObjectAsJSON(prefix []byte, value interface{}) (*Item, error)
- func (pq *PrefixQueue) EnqueueString(prefix, value string) (*Item, error)
- func (pq *PrefixQueue) Length() uint64
- func (pq *PrefixQueue) Peek(prefix []byte) (*Item, error)
- func (pq *PrefixQueue) PeekByID(prefix []byte, id uint64) (*Item, error)
- func (pq *PrefixQueue) PeekByIDString(prefix string, id uint64) (*Item, error)
- func (pq *PrefixQueue) PeekString(prefix string) (*Item, error)
- func (pq *PrefixQueue) Update(prefix []byte, id uint64, newValue []byte) (*Item, error)
- func (pq *PrefixQueue) UpdateObject(prefix []byte, id uint64, newValue interface{}) (*Item, error)
- func (pq *PrefixQueue) UpdateObjectAsJSON(prefix []byte, id uint64, newValue interface{}) (*Item, error)
- func (pq *PrefixQueue) UpdateString(prefix string, id uint64, value string) (*Item, error)
- type PriorityItem
Constants ¶
This section is empty.
Variables ¶
var ( // ErrEmpty is returned when the stack or queue is empty. ErrEmpty = errors.New("queue is empty") // ErrOutOfBounds is returned when the ID used to lookup an item // is outside of the range of the stack or queue. ErrOutOfBounds = errors.New("ID used is outside range of queue") // ErrDBClosed is returned when the Close function has already // been called, causing the stack or queue to close, as well as // its underlying database. ErrDBClosed = errors.New("Database is closed") )
Functions ¶
This section is empty.
Types ¶
type Item ¶
Item represents an entry in either a stack or queue.
func (*Item) ToObject ¶
ToObject decodes the item value into the given value type using encoding/gob.
The value passed to this method should be a pointer to a variable of the type you wish to decode into. The variable pointed to will hold the decoded object.
Objects containing pointers with zero values will decode to nil when using this function. This is due to how the encoding/gob package works. Because of this, you should only use this function to decode simple types.
func (*Item) ToObjectFromJSON ¶
ToObjectFromJSON decodes the item value into the given value type using encoding/json.
The value passed to this method should be a pointer to a variable of the type you wish to decode into. The variable pointed to will hold the decoded object.
type PrefixQueue ¶
PrefixQueue is a standard FIFO (first in, first out) queue that separates each given prefix into its own queue.
func OpenPrefixQueue ¶
func OpenPrefixQueue(db *leveldb.DB) (*PrefixQueue, error)
OpenPrefixQueue opens a prefix queue if one exists at the given directory. If one does not already exist, a new prefix queue is created.
func (*PrefixQueue) Close ¶
func (pq *PrefixQueue) Close() error
Close closes the LevelDB database of the prefix queue.
func (*PrefixQueue) Dequeue ¶
func (pq *PrefixQueue) Dequeue(prefix []byte) (*Item, error)
Dequeue removes the next item in the prefix queue and returns it.
func (*PrefixQueue) DequeueString ¶
func (pq *PrefixQueue) DequeueString(prefix string) (*Item, error)
DequeueString is a helper function for Dequeue that accepts the prefix as a string rather than a byte slice.
func (*PrefixQueue) Enqueue ¶
func (pq *PrefixQueue) Enqueue(prefix, value []byte) (*Item, error)
Enqueue adds an item to the queue.
func (*PrefixQueue) EnqueueObject ¶
func (pq *PrefixQueue) EnqueueObject(prefix []byte, value interface{}) (*Item, error)
EnqueueObject is a helper function for Enqueue that accepts any value type, which is then encoded into a byte slice using encoding/gob.
Objects containing pointers with zero values will decode to nil when using this function. This is due to how the encoding/gob package works. Because of this, you should only use this function to encode simple types.
func (*PrefixQueue) EnqueueObjectAsJSON ¶
func (pq *PrefixQueue) EnqueueObjectAsJSON(prefix []byte, value interface{}) (*Item, error)
EnqueueObjectAsJSON is a helper function for Enqueue that accepts any value type, which is then encoded into a JSON byte slice using encoding/json.
Use this function to handle encoding of complex types.
func (*PrefixQueue) EnqueueString ¶
func (pq *PrefixQueue) EnqueueString(prefix, value string) (*Item, error)
EnqueueString is a helper function for Enqueue that accepts the prefix and value as a string rather than a byte slice.
func (*PrefixQueue) Length ¶
func (pq *PrefixQueue) Length() uint64
Length returns the total number of items in the prefix queue.
func (*PrefixQueue) Peek ¶
func (pq *PrefixQueue) Peek(prefix []byte) (*Item, error)
Peek returns the next item in the given queue without removing it.
func (*PrefixQueue) PeekByID ¶
func (pq *PrefixQueue) PeekByID(prefix []byte, id uint64) (*Item, error)
PeekByID returns the item with the given ID without removing it.
func (*PrefixQueue) PeekByIDString ¶
func (pq *PrefixQueue) PeekByIDString(prefix string, id uint64) (*Item, error)
PeekByIDString is a helper function for Peek that accepts the prefix as a string rather than a byte slice.
func (*PrefixQueue) PeekString ¶
func (pq *PrefixQueue) PeekString(prefix string) (*Item, error)
PeekString is a helper function for Peek that accepts the prefix as a string rather than a byte slice.
func (*PrefixQueue) Update ¶
Update updates an item in the given queue without changing its position.
func (*PrefixQueue) UpdateObject ¶
func (pq *PrefixQueue) UpdateObject(prefix []byte, id uint64, newValue interface{}) (*Item, error)
UpdateObject is a helper function for Update that accepts any value type, which is then encoded into a byte slice using encoding/gob.
Objects containing pointers with zero values will decode to nil when using this function. This is due to how the encoding/gob package works. Because of this, you should only use this function to encode simple types.
func (*PrefixQueue) UpdateObjectAsJSON ¶
func (pq *PrefixQueue) UpdateObjectAsJSON(prefix []byte, id uint64, newValue interface{}) (*Item, error)
UpdateObjectAsJSON is a helper function for Update that accepts any value type, which is then encoded into a JSON byte slice using encoding/json.
Use this function to handle encoding of complex types.
func (*PrefixQueue) UpdateString ¶
UpdateString is a helper function for Update that accepts the prefix and value as a string rather than a byte slice.
type PriorityItem ¶
PriorityItem represents an entry in a priority queue.
func (*PriorityItem) ToObject ¶
func (pi *PriorityItem) ToObject(value interface{}) error
ToObject decodes the item value into the given value type using encoding/gob.
The value passed to this method should be a pointer to a variable of the type you wish to decode into. The variable pointed to will hold the decoded object.
Objects containing pointers with zero values will decode to nil when using this function. This is due to how the encoding/gob package works. Because of this, you should only use this function to decode simple types.
func (*PriorityItem) ToObjectFromJSON ¶
func (pi *PriorityItem) ToObjectFromJSON(value interface{}) error
ToObjectFromJSON decodes the item value into the given value type using encoding/json.
The value passed to this method should be a pointer to a variable of the type you wish to decode into. The variable pointed to will hold the decoded object.
func (*PriorityItem) ToString ¶
func (pi *PriorityItem) ToString() string
ToString returns the priority item value as a string.
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