What sets the do/tap operator apart from other observable operators?

Can anyone clarify the distinction in simple terms between the typical observable operators used for observing output and why do/tap appear to serve the same purpose? What is the reason for utilizing do/tap?

Answer №1

In RxJS v6+, the `do/tap` operator stands out from other operators because it does not modify the items that pass through it. The function results aren't used for further processing, making it a safe choice for executing code with side effects - actions that change a state outside of the Observable pipe. For instance, using `console.log` inside a `tap` function modifies the Browser's state when the function is called.

It's also recommended to make any necessary alterations to variables or attributes within the `tap` function before subscribing. This maintains the purity of the Observable pipe, ensuring consistent outputs for the same inputs.

Exercise caution when modifying the items emitted to the `tap` operator, as this will affect other pipes and alter the final outcome, compromising the purity once again.

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