fix(maybe): switch to dynamic import for rxjs in Maybe methods (#206)

Replaced `require` calls with dynamic `import` for `rxjs` within the `Maybe` class. This change modernizes the code by leveraging ES module syntax, enhancing module loading efficiency and ensuring compatibility with environments that prefer or enforce ES modules over CommonJS. Additionally, cleaned up imports in the test file `maybe.spec.ts` by removing redundant object destructuring.

Author: patrickmichalina

src/maybe/maybe.spec.ts

@@ -1,5 +1,6 @@
 import { maybe, none } from './public_api'
 import { Maybe } from './maybe'
+import { EMPTY, of, throwError } from 'rxjs'
 
 describe('Maybe', () => {
   describe('when returning a value with possible throw', () => {
@@ -721,7 +722,6 @@ describe('Maybe', () => {
 
   describe('flatMapObservable', () => {
     it('should handle a Some value with emitting observable', (done) => {
-      const { of } = require('rxjs')
       const hasSome = maybe(42)
       hasSome.flatMapObservable(value => of(`Value: ${value}`))
         .then(result => {
@@ -732,7 +732,6 @@ describe('Maybe', () => {
     })
 
     it('should handle a Some value with empty observable', (done) => {
-      const { EMPTY } = require('rxjs')
       const hasSome = maybe(42)
       hasSome.flatMapObservable(() => EMPTY)
         .then(result => {
@@ -742,7 +741,6 @@ describe('Maybe', () => {
     })
 
     it('should handle a Some value with erroring observable', (done) => {
-      const { throwError } = require('rxjs')
       const hasSome = maybe(42)
       hasSome.flatMapObservable(() => throwError(() => new Error('test error')))
         .then(result => {
@@ -752,7 +750,6 @@ describe('Maybe', () => {
     })
 
     it('should handle a None value', (done) => {
-      const { of } = require('rxjs')
       const hasNone = maybe<number>()
       hasNone.flatMapObservable(value => of(`Value: ${value}`))
         .then(result => {
@@ -781,7 +778,6 @@ describe('Maybe', () => {
     })
 
     it('should create a Maybe from Observable with static fromObservable', (done) => {
-      const { of } = require('rxjs')
       Maybe.fromObservable(of(42))
         .then(result => {
           expect(result.isSome()).toBe(true)
@@ -791,7 +787,6 @@ describe('Maybe', () => {
     })
 
     it('should create a Maybe from empty Observable with static fromObservable', (done) => {
-      const { EMPTY } = require('rxjs')
       Maybe.fromObservable(EMPTY)
         .then(result => {
           expect(result.isNone()).toBe(true)
@@ -800,7 +795,6 @@ describe('Maybe', () => {
     })
 
     it('should create a Maybe from erroring Observable with static fromObservable', (done) => {
-      const { throwError } = require('rxjs')
       Maybe.fromObservable(throwError(() => new Error('test error')))
         .then(result => {
           expect(result.isNone()).toBe(true)

src/maybe/maybe.ts

@@ -2,9 +2,9 @@ import type { IResult } from '../result/result.interface'
 import type { IMaybePattern, IMaybe } from './maybe.interface'
 import { FailResult, OkResult } from '../result/result'
 
-export class Maybe<T> implements IMaybe<T>  {
+export class Maybe<T> implements IMaybe<T> {
   constructor(private readonly value?: T | null) { }
-  
+
   public of(value: T): IMaybe<T> {
     return new Maybe<T>(value)
   }
@@ -98,19 +98,18 @@ export class Maybe<T> implements IMaybe<T>  {
    *   .then(name => displayUserName(name));
    */
   public static fromObservable<T>(observable: import('rxjs').Observable<T>): Promise<IMaybe<NonNullable<T>>> {
-    const { firstValueFrom, EMPTY } = require('rxjs')
-    const { take, map, catchError } = require('rxjs/operators')
-    
-    return firstValueFrom(
-      observable.pipe(
-        take(1),
-        map((value: unknown) => new Maybe<NonNullable<T>>(value as NonNullable<T>)),
-        catchError(() => EMPTY)
+    return import('rxjs').then(({ firstValueFrom, EMPTY, take, map, catchError }) => {
+      return firstValueFrom(
+        observable.pipe(
+          take(1),
+          map((value) => new Maybe<NonNullable<T>>(value as NonNullable<T>)),
+          catchError(() => EMPTY)
+        )
+      ).then(
+        (maybeValue: IMaybe<NonNullable<T>>) => maybeValue,
+        () => new Maybe<NonNullable<T>>()
       )
-    ).then(
-      (maybeValue: IMaybe<NonNullable<T>>) => maybeValue,
-      () => new Maybe<NonNullable<T>>()
-    )
+    })
   }
 
   /**
@@ -271,7 +270,7 @@ export class Maybe<T> implements IMaybe<T>  {
     if (this.isNone()) {
       return Promise.resolve(new Maybe<NonNullable<R>>())
     }
-    
+
     return fn(this.value as NonNullable<T>)
       .then((value: R) => new Maybe<NonNullable<R>>(value as NonNullable<R>))
       .catch(() => new Maybe<NonNullable<R>>())
@@ -281,11 +280,7 @@ export class Maybe<T> implements IMaybe<T>  {
     if (this.isNone()) {
       return Promise.resolve(new Maybe<NonNullable<R>>())
     }
-    
-    const { firstValueFrom, EMPTY } = require('rxjs')
-    const { take, map, catchError } = require('rxjs/operators')
-    
-    return firstValueFrom(
+    return import('rxjs').then(({ firstValueFrom, EMPTY, take, map, catchError }) => firstValueFrom(
       fn(this.value as NonNullable<T>).pipe(
         take(1),
         map((value: unknown) => new Maybe<NonNullable<R>>(value as NonNullable<R>)),
@@ -294,7 +289,7 @@ export class Maybe<T> implements IMaybe<T>  {
     ).then(
       (maybeValue: IMaybe<NonNullable<R>>) => maybeValue,
       () => new Maybe<NonNullable<R>>()
-    )
+    ))
   }
 
   public flatMapMany<R>(fn: (val: NonNullable<T>) => Promise<R>[]): Promise<IMaybe<NonNullable<R>[]>> {