Improve readme wording

Closes #84

Author: sindresorhus

index.d.ts

@@ -15,7 +15,7 @@ export type Options = BaseOptions & {
 
 	When `false`, instead of stopping when a promise rejects, it will wait for all the promises to settle and then reject with an [`AggregateError`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError) containing all the errors from the rejected promises.
 
-	Caveat: When `true`, any already-started async mappers will continue to run until they resolve or reject. In the case of infinite concurrency with sync iterables, *all* mappers are invoked on startup and will continue after the first rejection. [Issue #51](https://github.com/sindresorhus/p-map/issues/51) can be implemented for abort control.
+	Caveat: When `true`, any already-started async mappers will continue to run until they resolve or reject. In the case of infinite concurrency with sync iterables, *all* mappers are invoked on startup and will continue after the first rejection. Use the `signal` option for abort control.
 
 	@default true
 	*/
@@ -41,7 +41,7 @@ export type Options = BaseOptions & {
 	// Throws AbortError (DOMException) after 500 ms.
 	```
 	*/
-	readonly signal?: AbortSignal;
+	readonly signal?: AbortSignal | undefined;
 };
 
 export type IterableOptions = BaseOptions & {
@@ -71,7 +71,7 @@ export type Mapper<Element = any, NewElement = unknown> = (
 /**
 @param input - Synchronous or asynchronous iterable that is iterated over concurrently, calling the `mapper` function for each element. Each iterated item is `await`'d before the `mapper` is invoked so the iterable may return a `Promise` that resolves to an item. Asynchronous iterables (different from synchronous iterables that return `Promise` that resolves to an item) can be used when the next item may not be ready without waiting for an asynchronous process to complete and/or the end of the iterable may be reached after the asynchronous process completes. For example, reading from a remote queue when the queue has reached empty, or reading lines from a stream.
 @param mapper - Function which is called for every item in `input`. Expected to return a `Promise` or value.
-@returns A `Promise` that is fulfilled when all promises in `input` and ones returned from `mapper` are fulfilled, or rejects if any of the promises reject. The fulfilled value is an `Array` of the fulfilled values returned from `mapper` in `input` order.
+@returns A `Promise` that is fulfilled when all promises in `input` and the ones returned from `mapper` are fulfilled, or rejects if any of the promises reject. The fulfilled value is an `Array` of the fulfilled values returned from `mapper` in `input` order.
 
 @example
 ```

readme.md

@@ -39,7 +39,7 @@ console.log(result);
 
 ### pMap(input, mapper, options?)
 
-Returns a `Promise` that is fulfilled when all promises in `input` and ones returned from `mapper` are fulfilled, or rejects if any of the promises reject. The fulfilled value is an `Array` of the fulfilled values returned from `mapper` in `input` order.
+Returns a `Promise` that is fulfilled when all promises in `input` and the ones returned from `mapper` are fulfilled, or rejects if any of the promises reject. The fulfilled value is an `Array` of the fulfilled values returned from `mapper` in `input` order.
 
 ### pMapIterable(input, mapper, options?)
 
@@ -103,7 +103,7 @@ When `true`, the first mapper rejection will be rejected back to the consumer.
 
 When `false`, instead of stopping when a promise rejects, it will wait for all the promises to settle and then reject with an [`AggregateError`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/AggregateError) containing all the errors from the rejected promises.
 
-Caveat: When `true`, any already-started async mappers will continue to run until they resolve or reject. In the case of infinite concurrency with sync iterables, *all* mappers are invoked on startup and will continue after the first rejection. [Issue #51](https://github.com/sindresorhus/p-map/issues/51) can be implemented for abort control.
+Caveat: When `true`, any already-started async mappers will continue to run until they resolve or reject. In the case of infinite concurrency with sync iterables, *all* mappers are invoked on startup and will continue after the first rejection. Use the `signal` option for abort control.
 
 ##### signal