Reduce, Aggregate and Flatmap Operators of Sequencing

Learn to operate the reduce, aggregate and flatMap operators of sequencing.


The reduce operator, also known as fold, takes an Observable and returns a new one that always contains a single item, which is the result of applying a function over each element. This function receives the current element and the result of the function’s previous invocation.

Note: The reduce function has another parameter that is optional and can be used to pass a starting seed value.

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