Array indexing

[ParadaCarleton]

Feature request/suggestion: Reformatting code that assumes a particular indexing for an array, e.g. for i in 1:length(array) instead of for i in eachindex(array).

(Should probably be a style feature that you can enable/disable.)

[domluna]

can you expand a little more I'm not sure what you mean

[ParadaCarleton]

can you expand a little more I'm not sure what you mean

Some people will sometimes write code that assumes an array is indexed 1:length(array). For instance, if I'm iterating over an array, I might write:

for i in 1:length(array)
    f(array[i])
end

However, this can run into problems with some arrays that have unusual indexing, like the indices introduced by OffsetArrays.jl. In addition, arrays with multiple dimensions in base can sometimes be indexed more quickly by using eachindex(array), since it gives the compiler the ability to reorder some indices. It's therefore better to write something like:

for i in eachindex(array)
    f(array[i])
end

[domluna]

oh i see. I don't think this makes sense as an option since it's a pretty niche transform and they are not semantically equivalent (right?) which could cause other issues

[extradosages]

Don't think you can do this generally without statically inferring types and which method is going to be dispatched.

[penelopeysm]

IMO, JuliaFormatter should not be doing transformations that can change semantics. Such transformations should be provided by a different tool, like a linter (see, e.g., clang-format vs clang-tidy).