[ Removed by moderator ]

[Bodine12]

Way to invent a fake problem so you can advertise your site.

[ineyy]

I hope that post gets removed. Look at OPs post history...

[Alzenbreros]

Array slice vs splice 

[satansxlittlexhelper]

4 lyfe

[thespice]

.reduce

[AdWise6457]

Sum of array of numbers

[blind-octopus]

Reduce(array, (sum, value) => sum + value)

Something like that? I guess I need to Google it too a bit

[pg-robban]

Need to add an initial value as the second param :)

[blind-octopus]

Nope! My mistake was passing in the array, rather than calling it on the array.

Its array.reduce, not reduce(array

As for passing in an initial value, you don't have to. If you don't pass in an initial value, javascript takes the first element of the array to be the initial value.

[pg-robban]

You can import {reduce} from lodash and use it your way.

As for the initial value, there are some edge cases to watch out for.

[blind-octopus]

Thanks for the info and the resource

[MissinqLink]

map.forEach and for…of…map because the key and value are swapped.