HashMap

Destructor

A destructor is present on this object, but not explicitly documented in the source.

Postblit

A postblit is present on this object, but not explicitly documented in the source.

Members

Aliases

require

alias require = getOrAdd

Functions

addIfMissed

bool addIfMissed(K k, T value)

Add key/value to hash if key is not in table. value can be lazy/callable.

byKey

auto byKey()

iterator by keys

byPair

auto byPair()

iterator by key/value pairs

byValue

auto byValue()

iterator by values

capacity

auto capacity()

when capacity == 0 - next put for new key can trigger resize

clear

void clear()

throw away all keys

dump

string dump()

dump HashMap content to string (for debugging)

fetch

auto fetch(K k)

fetch is safe(do not return pointer) and nogc (do not throw exception) variant of "in" but retuns tuple("ok", "value"). You can check if result.ok == true. It this case you'll find value in "value"

get

V get(K k, T defaultValue)

get with default value it infers @safe, @nogc from user data: do not return ptr and do not thow

getOrAdd

V getOrAdd(K k, T defaultValue)

get value from hash or add if key is not in table. defaultValue can be callable.

grow_factor

auto grow_factor()

get current grow factor.

grow_factor

void grow_factor(int gf)

set grow factor (can be between 2, 4 or 8).

length

auto length()

get numter of keys in table

opBinaryRight

deprecated auto opBinaryRight(K k)

key in table

opBinaryRight

deprecated auto opBinaryRight(K k)

"in" is unsafe as it can point to arbitrary address after resize

opIndex

auto opIndex(K k)

mapkey Attention: you can't use this method in @nogc code. Usual aakey method. Throws exception if key not found

opIndexAssign

void opIndexAssign(V v, K k)

mapk = v;

put

auto put(K k, V v)

put pair (k,v) into hash.

remove

bool remove(K k)

remomve key from hash.

size

auto size()

get current buckets number

import std.range;
import std.algorithm;
import std.experimental.logger;
HashMap!(string, int) counter;
string[] words = [
    "hello", "this", "simple", "example", "should", "succeed", "or", "it",
    "should", "fail"
];
// count words, simplest and fastest way
foreach (word; words) {
    counter[word] = counter.getOrAdd(word, 0) + 1;
}
assert(!counter.fetch("world").ok);
assert(counter.fetch("hello").value == 1);
assert(counter["hello"] == 1);
assert(counter["should"] == 2);
assert(counter.contains("hello"));
assert(counter.length == words.length - 1);
// iterators
assert(counter.byKey.count == counter.byValue.count);
assert(words.all!(w => counter.contains(w))); // all words are in table
assert(counter.byValue.sum == words.length); // sum of counters must equals to number of words

• KeyNotFound
• KeyRemoved

• HashMap