‘of’ vs ‘from’ operator

It is important to note the difference between of and from when passing an array-like structure (including strings):

Observable.of([1, 2, 3]).subscribe(x => console.log(x));

would print the whole array at once.

On the other hand,

Observable.from([1, 2, 3]).subscribe(x => console.log(x));

prints the elements 1 by 1.

For strings the behaviour is the same, but at character level.

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