Thanks for this explanation! I have a question on filter/map ect (I'm a JS dev). Do they loop through the whole Collection again and again ? (i.e, the first filter do, then the map do, then the second filter do...).
Alain, thanks for your answer. It's really clear and enriching.
Hi Maxime,
Note that the following is specific to JS. It may work similar or quite different in other languages.
To answer your question, try the following code
[1,2,3,4,5] .map(x => { console.log("A", x); return x; }) .map(y => console.log("B", y))
This outputs
A 1 A 2 A 3 A 4 A 5 B 1 B 2 B 3 B 4 B 5
That shows that in JS, a regular array map operation iterates over the entire array before passing it on to the next operation.
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Thanks for this explanation!
I have a question on filter/map ect (I'm a JS dev). Do they loop through the whole Collection again and again ? (i.e, the first filter do, then the map do, then the second filter do...).
Alain, thanks for your answer. It's really clear and enriching.
Hi Maxime,
Note that the following is specific to JS. It may work similar or quite different in other languages.
To answer your question, try the following code
This outputs
That shows that in JS, a regular array map operation iterates over the entire array before passing it on to the next operation.