Hash Table Implementation for javascript
npm install ht
ht is a HashTable implementation in javascript that can be used in both node and the browser.
``
npm install ht
Or download the source (minified)
Note ht depends on declare.js, extended, is-extended, and array-extended
To create a new HashTable
`javascript`
var Ht = require("ht");
var ht = new Ht();
put(key, value)
Adds a new key value pair to the hash table, ht supports any value as a key.
`javascript
var key = {}, key2 = {};
ht.put(key, "value1");
ht.put(key2, "value2");
ht.get(key); //"value1";
ht.get(key2); //"value2";
`
If your key contains a hashCode, function then that will be used to put the key value pair into the hash table.
`javascript
function Person(first, last){
this.firstName = first;
this.lastName = last;
}
Person.prototype.hashCode = function(){
return this.firstName + this.lastName;
}
ht.put(new Person("bob", "yukon"), "this is bob");
ht.put(new Person("sally", "yukon"), "this is sally");
ht.get(new Person("bob", "yukon")); //"this is bob"
`
get(key)
Get a a value based on the key.
`javascript
ht.put(new Date(2013, 1, 22), "value1");
ht.put(new Date(2013, 1, 23), "value2");
ht.get(new Date(2013, 1, 22)); //"value1";
ht.get(new Date(2013, 1, 23); //"value2";
`
set(key)
Set a a value based on the key.
`javascript
ht.put(new Date(2013, 1, 22), "value1");
ht.put(new Date(2013, 1, 23), "value2");
ht.get(new Date(2013, 1, 22)); //"value1";
ht.get(new Date(2013, 1, 23); //"value2";
ht.set(new Date(2013, 1, 22), "new value1");
ht.set(new Date(2013, 1, 23), "new value2");
ht.get(new Date(2013, 1, 22)); //"new value1";
ht.get(new Date(2013, 1, 23); //"new value2";
`
remove(key)
Removes a key value pair.
`javascript
ht.put(new Date(2013, 1, 22), "value1");
ht.put(new Date(2013, 1, 23), "value2");
ht.get(new Date(2013, 1, 22)); //"value1";
ht.get(new Date(2013, 1, 23); //"value2";
ht.remove(new Date(2013, 1, 22)); //"value1";
ht.remove(new Date(2013, 1, 23); //"value2";
ht.get(new Date(2013, 1, 22)); //null;
ht.get(new Date(2013, 1, 23); //null";
`
contains(key)
Returns true or false if the table does or does not contain a given key value pair.
`javascript
ht.put(new Date(2013, 1, 22), "value1");
ht.put(new Date(2013, 1, 23), "value2");
ht.contains(new Date(2013, 1, 22)); //true;
ht.contains(new Date(2013, 1, 23); //true;
`
concat(hashTable
Concats two hash tables together into a new one.
`javascript
var ht1 = new Ht(), ht2 = new Ht();
ht1.put(new Date(2013, 1, 22), "value1");
ht1.put(new Date(2013, 1, 23), "value2");
var key = {}, key2 = {};
ht2.put(key, "value1");
ht2.put(key2, "value2");
var ht3 = ht1.concat(ht2);
ht3.contains(key); //true
ht3.contains(key2); //true
ht1.contains(new Date(2013, 1, 22)); //true
ht1.contains(new Date(2013, 1, 23)); //true
`
clear
Clear all items from the hash table
`javascript
ht.put("key1", "value1");
ht.put("key2", "value2");
ht.clear();
ht.contains("key1"); //false
ht.contains("key2"); //false
`
keys
Returns an array of all keys in the table.
`javascript
ht.put("key1", "value1");
ht.put("key2", "value2");
ht.keys(); //["key1", "key2"]
`
values
Gets all values in the hash table.
`javascript
ht.put("key1", "value1");
ht.put("key2", "value2");
ht.values(); //["value1", "value2"]
`
entrySet
Returns an array of all key value pairs in the table.
`javascript
ht.put("key1", "value1");
ht.put("key2", "value2");
ht.entrySet(); //[{key: "key1", value: "value1"}, {key: "key2", value: "value2"}]
`
isEmpty
Returns true if the table contains any values, false otherwise.
`javascript
var ht = new Ht();
ht.isEmpty(); //true
ht.put("key1", "value1");
ht.put("key2", "value2");
ht.isEmpty(); //false
`
Each hash table contains the following array like methods.
Note each method will pass a key and value to the iterator instead of a value and index.
`javascript
ht.put("key1", "value1");
ht.put("key2", "value2");
ht.forEach(function(key, value){
console.log(key + " : " + value);
});
`
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