docs(readme): minor edits

README.md

@@ -122,7 +122,16 @@ It also provides implementations of `EqualFunction` for objects, iterables, maps
 
 ## Reducers
 
-The library exports a type `Reducer` which is like a regular reducer, but can return `undefined` to stop the iteration short, and which is used by functions [`reduceIterable`](https://github.com/ivan7237d/antiutils/blob/master/src/internal/iterable/reduceIterable.ts) and [`scanIterable`](https://github.com/ivan7237d/antiutils/blob/master/src/internal/iterable/scanIterable.ts).
+The library exports a type
+
+```ts
+type Reducer<Accumulator, Element> = (
+  accumulator: Accumulator,
+  element: Element,
+) => Accumulator | undefined;
+```
+
+which is like a regular reducer, but can return `undefined` to stop the iteration short, and which is used by functions [`reduceIterable`](https://github.com/ivan7237d/antiutils/blob/master/src/internal/iterable/reduceIterable.ts) and [`scanIterable`](https://github.com/ivan7237d/antiutils/blob/master/src/internal/iterable/scanIterable.ts).
 
 The library includes [basic implementations of this type](https://github.com/ivan7237d/antiutils/blob/master/src/internal/reducer), all of which except the boolean ones (`andReducer` and `orReducer`) can also be used with arrays and observables.