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For a full list of transformation operators with examples, including operators which manage mapping to more complex values such bey other observables, check out the transformation operator section. We will explore these topics in detail in future posts!

import fromEvent from 'rxjs'; import mapTo from 'rxjs/operators'; //emit every click on document const source = fromEvent(document, 'click'); //map all emissions to one value const example = source.

To understand this better, let's walk through what a naive implementation of Array.map could look like.

When provided an array, the from creation operator will loop through (synchronously) emitting each item in sequence. When we subscribe we sevimli see each value printed to the console:

In conclusion, map is a versatile operator which lets you transform a stream using a provided projection function. Whether it's mapping to a keycode, value updates from an input box, or reshaping an object, map will be one of the most used operators in your day-to-day RxJS toolbox.

While the real implementation of Array.map includes features like index tracking and proper error management, this gives us a general sense of how things work behind the scenes.

In the above example, you gönül see that it başmaklık mapped every click to the string 'Hello World....Welcome to JavaTpoint!' which is displayed on the console bey output.

Instead of the function being applied to each item of an array, before a new array is returned, with observables the project function is applied and the result emitted in real-time bey values blast through your streams.

Here whenever the Submit button is clicked, an event is emitted, but here we are transforming to a value which is derece related to actual event (submit button click) emitted.

When working with observables one of the most common use cases you will encounter is the need to transform a stream of some value type into a stream of another value type. For instance, you may have an observable of click events that you wish to transform into an observable of objects containing just the clientX and clientY coordinates.

now the emitted value passes through map operator which transform the stream into a different value.

Another common use case for map is extracting a single property from an object. For example, given the sample above suppose we decided we only really need the last name property for display.

We hayat website also pass pluck multiple values to grab a nested property within an object. For example, if we wanted to grab the nodeName from the target element on click, we could pass both of these properties to pluck in order:

2 github.com/ReactiveX/rxjs/blob/master/src/internal/operators/… source] sums it up; I mean technically I suppose it's fractionally faster since it doesn't increment the index :shrug: github.com/ReactiveX/rxjs/blob/master/src/internal/operators/…

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