@esfx/collections-sortedmap Package
Provides the SortedMap class, a collection class that utilizes @esfx/collection-core and @esfx/equatable.
Installation
npm i @esfx/collections-sortedmap
Usage
import { SortedMap } from "@esfx/collections-sortedmap";
import { Equatable, Equaler, Comparable, Comparer } from "@esfx/equatable";
class Person {
firstName: string;
lastName: string;
constructor(firstName: string, lastName: string) {
this.firstName = firstName;
this.lastName = lastName;
}
toString() {
return `${this.firstName} ${this.lastName}`;
}
[Equatable.equals](other: unknown) {
return other instanceof Person
&& this.lastName === other.lastName
&& this.firstName === other.firstName;
}
[Equatable.hash]() {
return Equaler.defaultEqualer.hash(this.lastName)
^ Equaler.defaultEqualer.hash(this.firstName);
}
[Comparable.compareTo](other: unknown) {
if (!(other instanceof Person)) throw new TypeError();
return Comparer.defaultComparer.compare(this.lastName, other.lastName)
|| Comparer.defaultComparer.compare(this.firstName, other.firstName);
}
}
const obj1 = new Person("Alice", "Johnson");
const obj2 = new Person("Bob", "Clark");
// ECMAScript native map iterates in insertion order
const map = new Map<Person, string>(); // native ECMAScript Map
map.set(obj1, "obj1");
map.set(obj2, "obj2");
[...map.keys()]; // Alice Johnson, Bob Clark
// SortedMap uses Comparable.compareTo if available
const sortedMap = new SortedMap<Person, string>();
sortedMap.set(obj1, "obj1");
sortedMap.set(obj2, "obj2");
[...sortedMap.keys()]; // Bob Clark, Alice Johnson