StackMap

StackMap extends the basic hashmap type by adding a limit to the number of items contained at any given time. In addition, StackMap retains the order in which elements were added, and employs that during foreach() traversal. Additions to the map beyond the capacity will result in an exception being thrown.

You can push and pop things just like an typical stack, and/or traverse the entries in the order they were added, though with the additional capability of retrieving and/or removing by key.

Note also that a push/add operation will replace an existing entry with the same key, exposing a twist on the stack notion.

class StackMap (

alias Hash = Container.hash

alias Reap = Container.reap

alias Heap = Container.Collect

) {

this(size_t capacity);

~this();

static void reaper(K k, R r);

size_t size [@property getter];

void clear();

bool push(K key, V value);

bool popHead(K key, V value);

bool popTail(K key, V value);

int opApply(int delegate(ref K key, ref V value) dg);

bool add(K key, V value);

bool get(K key, V value);

bool take(K key, V value);

}

Constructors

this this(size_t capacity): Construct a cache with the specified maximum number of entries. Additions to the cache beyond this number will throw an exception

Destructor

~this ~this(): clean up when done

Members

Functions

add bool add(K key, V value): Place an entry into the cache and associate it with the provided key. Note that there can be only one entry for any particular key. If two entries are added with the same key, the second effectively overwrites the first.
clear void clear()
get bool get(K key, V value): Get the cache entry identified by the given key
opApply int opApply(int delegate(ref K key, ref V value) dg): Iterate from the oldest to the most recent additions
popHead bool popHead(K key, V value): Remove and return the more recent addition to the stack
popTail bool popTail(K key, V value): Remove and return the oldest addition to the stack
push bool push(K key, V value): Place an entry into the cache and associate it with the provided key. Note that there can be only one entry for any particular key. If two entries are added with the same key, the second effectively overwrites the first.
take bool take(K key, V value): Remove (and return) the cache entry associated with the provided key. Returns false if there is no such entry.

Properties

size size_t size [@property getter]

Static functions

reaper void reaper(K k, R r): Reaping callback for the hashmap, acting as a trampoline