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To do this we could apply the map operator, providing a function that returns an object with just these properties:

I am trying to understand the difference between map and mapTo in Kotlin. What is the difference using some examples?

The RxJS operator map kişi be used to map the stream value to a new value. However, if you want to map to a static value that does not depend on the stream value, you birey use the mapTo operator. This operator accepts the value directly and you don't need to create an additional function.

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

Lastly, there may also be times where you always want to map to a single value, no matter the input. For these situations, you gönül use the mapTo operator.

Emits the given constant value on the output Observable every time the source Observable emits a value.

These two Qatar flights with slightly different times and different flight number must actually be the same flight, right?

I'm reading the docs for mapTo and I'm simply not getting the point of that operator's existence. I get what it does but the two line below should produce equivalent result.

map operator is used when we want to transform a stream into a value which is derece related to the emitted stream.

RxJS mapTo() operator is a transformation operator that emits a constant value kakım an output along with the Observable whenever the source Observable emits a value.

For situations where you find yourself always wanting to map to a specific value, one way you could handle it is by simply using map and ignoring the input:

On the other hand map: Returns a list containing the results of applying the given transform function to each element in the original array.

If you have spent time working with JavaScript arrays you may already be click here familiar with Array.map. When dealing with arrays, the map method lets you transform an array by applying a provided function (often referred to kakım a 'projection' function) to each item within the array. For instance, let's say we have an array of numbers 1-5:

While this works, the wrapping function isn't necessary since we are ignoring the received value. For these scenarios you birey replace map with mapTo, and simply provide the value you wish to return on all emissions:

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