@stnekroman/tstools/dist/optional/Optional.js

Set of handy tools for TypeScript development

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.Optional = void 0;
const Objects_1 = require("../Objects");
const NoSuchElementException_1 = require("./NoSuchElementException");
class Optional {
    constructor(value) {
        this.value = value;
    }
    static of(value) {
        if (Objects_1.Objects.isNotNullOrUndefined(value)) {
            return new Optional(value);
        }
        else {
            return Optional.EMPTY;
        }
    }
    static empty() {
        return Optional.EMPTY;
    }
    get() {
        if (this.isPresent()) {
            return this.value;
        }
        throw new NoSuchElementException_1.NoSuchElementException('No value present');
    }
    isPresent() {
        return Objects_1.Objects.isNotNullOrUndefined(this.value);
    }
    isEmpty() {
        return Objects_1.Objects.isNullOrUndefined(this.value);
    }
    filter(filterFn) {
        if (this.isEmpty()) {
            return this;
        }
        else {
            return filterFn(this.value) ? this : Optional.EMPTY;
        }
    }
    map(mapper) {
        if (this.isEmpty()) {
            return Optional.EMPTY;
        }
        else {
            return Optional.of(mapper(this.value));
        }
    }
    flatMap(mapper) {
        if (this.isEmpty()) {
            return Optional.EMPTY;
        }
        else {
            return mapper(this.value);
        }
    }
    mapAsync(mapper) {
        if (this.isEmpty()) {
            return Promise.resolve(Optional.EMPTY);
        }
        else {
            return mapper(this.value).then((r) => Optional.of(r));
        }
    }
    or(provider) {
        if (this.isPresent()) {
            return this;
        }
        else {
            return provider();
        }
    }
    orElse(other) {
        return this.isPresent() ? this.value : other;
    }
    orElseGet(provider) {
        return this.isPresent() ? this.value : provider();
    }
    orElseThrow(provider) {
        if (this.isEmpty()) {
            throw provider ? provider() : new NoSuchElementException_1.NoSuchElementException('No value present');
        }
        return this.value;
    }
    toString() {
        return this.isPresent() ? `Optional[${this.value}]` : 'Optional.empty';
    }
    equals(another) {
        if (this == another ||
            (this.isEmpty() && another.isEmpty()) ||
            (isNaN(this.value) && isNaN(another.value))) {
            return true;
        }
        return this.value === another.value;
    }
    property(key) {
        return Optional.of(this.value[key]);
    }
}
exports.Optional = Optional;
Optional.EMPTY = new Optional(undefined);