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Suppose I have a list

{a, b, c, d} 

I want to operate on this list with a function which depends on the index of the element, e.g. I want to add the index number to each element to get

{a+1, b+2, c+3, d+4}

what would be the best way to do this?

I have seen some possible approaches but was wondering what the 'canonical' way would be.

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MapIndexed:

MapIndexed[#2[[1]] + # &, {a, b, c, d}]

{1 + a, 2 + b, 3 + c, 4 + d}

Also

Range[Length @ #] + # & @ {a,b,c,d}

{1 + a, 2 + b, 3 + c, 4 + d}

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A couple more options --

lst = {a, b, c, d};

Table[lst[[n]] + n, {n, Length[lst]}]

{1 + a, 2 + b, 3 + c, 4 + d}

lst + Range[Length[lst]]

{1 + a, 2 + b, 3 + c, 4 + d}

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