# Is there a way to turn off the warnings "indexing with indices obtained from 'length','size' etc is discouraged in VSCode?

**URL:** <https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093>\
**Category:** General Usage\
**Created:** [August 1, 2022, 8:41am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093 "2022-08-01T08:41:34Z")\
**Posts on this page:** 15\
**Page:** 1

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**Author:** ![Steven\_Sagaert](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/steven_sagaert/32/29578_2.png) [@Steven\_Sagaert](https://discourse.julialang.org/u/Steven_Sagaert)\
**Post date:** [August 1, 2022, 8:41am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/1 "2022-08-01T08:41:34Z")

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I get that you want these warnings for package writers but this is an application using Base matrices and it’s never going to use any other matrices with exotic indexing and you can’t pass matrices as an argument to the app. So I don’t need to change my code to generic abstract indexing and the warnings are just a nuisance.

Is there any way to turn these warnings off?

Also on a more general note: now that the community has decided that “anything goes” as far as indexing is concerned, I think that the type hierarchy for matrices should be way more detailed and reflect the indexing sheme of a matrix type. For example for Base matrices it should become something like OneBasedIndexingMatrix{.,.} instead of just Matrix{.,.} and when the compiler/linter sees this it won’t issue these warnings if you just use one based indexing directly instead of eachindex.

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**Author:** ![pfitzseb](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/pfitzseb/32/45566_2.png) [@pfitzseb](https://discourse.julialang.org/u/pfitzseb)\
**Post date:** [August 1, 2022, 8:42am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/2 "2022-08-01T08:42:45Z")

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> [@Steven\_Sagaert](#):
>
> Is there any way to turn these warnings off?

~~No, but there will be in the next release.~~ Yes, disable the `julia.lint.iter` check in the settings.

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**Author:** ![DNF](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dnf/32/10191_2.png) [@DNF](https://discourse.julialang.org/u/DNF)\
**Post date:** [August 1, 2022, 8:51am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/3 "2022-08-01T08:51:08Z")

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But isn’t this a good reminder to just get into the habit of using `eachindex`? Why would one ever want to use `1:length(x)`? Is it that the warnings are annoying for legacy code? (Personally, I never tolerate `1:length`, even when it is operating on an `Array` defined right inside the code itself.)

I don’t know if this is the case, but perhaps it is easier to automatically disable bounds checking with `eachindex` than with `1:length`?

Being able to disable linter messages is of course good in general.

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**Author:** ![Steven\_Sagaert](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/steven_sagaert/32/29578_2.png) [@Steven\_Sagaert](https://discourse.julialang.org/u/Steven_Sagaert)\
**Post date:** [August 1, 2022, 9:03am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/4 "2022-08-01T09:03:31Z")

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Why should I be forced to change code that was written at julia 0.2 when matrices were always 1-based and eachindex didn’t even exist, that is working fine and is as generic as it needs to be (like I said : it’s never going to use anything other than 1-based indices). It’s not like I hardcoded that a matrix is alway s N rows/columns long! It’s flexible with length and type so that’s plenty of generic.

It’s not because Python refugees couldn’t wrap their heads around 1-based indexing and wanted 0-based indexing (offset indexing) that all of a sudden perfectly correct 1-based indexing is wrong! Ok I get that it actually serves a more general role now than just 0-base indexing (but that’s how it got started) and it’s good that it’s possbile for more exotic things but you shouldn’t force the more exotic corner cases on everybody else.

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<div class="post-metadata">

**Author:** ![DNF](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dnf/32/10191_2.png) [@DNF](https://discourse.julialang.org/u/DNF)\
**Post date:** [August 1, 2022, 9:37am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/5 "2022-08-01T09:37:06Z")

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> [@Steven\_Sagaert](#):
>
> Why should I be forced

Since I didn’t argue for that (and you’re not being forced, anyway), I guess that is not for me to answer. Legacy code is different from new code, so removing the annoyance is reasonable.

> [@Steven\_Sagaert](#):
>
> you shouldn’t force the more exotic corner cases on everybody else.

It’s not an exotic corner case, though, but the _general_ case.

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<div class="post-metadata">

**Author:** ![pfitzseb](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/pfitzseb/32/45566_2.png) [@pfitzseb](https://discourse.julialang.org/u/pfitzseb)\
**Post date:** [August 1, 2022, 9:44am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/6 "2022-08-01T09:44:45Z")

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> [@pfitzseb](#):
>
> No, but there will be in the next release.

Nevermind, this check can be disabled with the `julia.lint.iter` setting.

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<div class="post-metadata">

**Author:** ![Soldalma](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/soldalma/32/29388_2.png) [@Soldalma](https://discourse.julialang.org/u/Soldalma)\
**Post date:** [August 3, 2022, 11:56pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/7 "2022-08-03T23:56:24Z")

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I dropped all `1:length(x)` I had, but what do I do with a few `2:length(x)` that are scattered in my code?

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<div class="post-metadata">

**Author:** ![PeterSimon](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/petersimon/32/25193_2.png) [@PeterSimon](https://discourse.julialang.org/u/PeterSimon)\
**Post date:** [August 4, 2022, 1:42am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/8 "2022-08-04T01:42:07Z")

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Here’s one approach:

```julia
julia> eachbutfirstindex(x) = Base.Iterators.peel(eachindex(x))[2]
eachbutfirstindex (generic function with 1 method)

julia> x = [5, 4, 3]
3-element Vector{Int64}:
 5
 4
 3

julia> for i in eachbutfirstindex(x)
         println((i,x[i]))
       end
(2, 4)
(3, 3)

```

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<div class="post-metadata">

**Author:** ![Paul\_Soderlind](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/paul_soderlind/32/1753_2.png) [@Paul\_Soderlind](https://discourse.julialang.org/u/Paul_Soderlind)\
**Post date:** [August 4, 2022, 7:03am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/9 "2022-08-04T07:03:39Z")

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perhaps: `firstindex(x)+1:lastindex(x)`?

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<div class="post-metadata">

**Author:** ![DNF](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dnf/32/10191_2.png) [@DNF](https://discourse.julialang.org/u/DNF)\
**Post date:** [August 4, 2022, 8:40am UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/10 "2022-08-04T08:40:34Z")

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Yeah, or, if it’s inside an indexing operation: `x[begin+1:end]`.

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<div class="post-metadata">

**Author:** ![PeterSimon](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/petersimon/32/25193_2.png) [@PeterSimon](https://discourse.julialang.org/u/PeterSimon)\
**Post date:** [August 4, 2022, 1:41pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/11 "2022-08-04T13:41:04Z")

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The reason that I didn’t suggest `firstindex(x)+1` as the starting index is that it would fail when `firstindex(x)` returns a `CartesianIndex`:

```julia
julia> CartesianIndex(1,1) + 1
ERROR: MethodError: no method matching +(::CartesianIndex{2}, ::Int64)
Closest candidates are:
  +(::Any, ::Any, ::Any, ::Any...) at ~/.julia/juliaup/julia-1.7.3+0.x64/share/julia/base/operators.jl:655
  +(::T, ::T) where T<:Union{Int128, Int16, Int32, Int64, Int8, UInt128, UInt16, UInt32, UInt64, UInt8} at ~/.julia/juliaup/julia-1.7.3+0.x64/share/julia/base/int.jl:87
  +(::T, ::Integer) where T<:AbstractChar at ~/.julia/juliaup/julia-1.7.3+0.x64/share/julia/base/char.jl:237
  ...
Stacktrace:
 [1] top-level scope
   @ REPL[2]:

```

I’m not sure how often this would arise in practice, though.

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<div class="post-metadata">

**Author:** ![PeterSimon](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/petersimon/32/25193_2.png) [@PeterSimon](https://discourse.julialang.org/u/PeterSimon)\
**Post date:** [August 4, 2022, 2:00pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/12 "2022-08-04T14:00:45Z")

</div>

Another pattern for consideration:

```julia
for i in eachindex(x)
    i == firstindex(x) && continue
    ...
end

```

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<div class="post-metadata">

**Author:** ![DNF](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dnf/32/10191_2.png) [@DNF](https://discourse.julialang.org/u/DNF)\
**Post date:** [August 4, 2022, 2:33pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/13 "2022-08-04T14:33:31Z")

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> [@PeterSimon](#):
>
> it would fail when `firstindex(x)` returns a `CartesianIndex`:

For multi-dimensional arrays, you can use `firstindex(x, dim)`.

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<div class="post-metadata">

**Author:** ![PeterSimon](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/petersimon/32/25193_2.png) [@PeterSimon](https://discourse.julialang.org/u/PeterSimon)\
**Post date:** [August 4, 2022, 2:39pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/14 "2022-08-04T14:39:57Z")

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Is that assuming we’re iterating over a single dimension?

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<div class="post-metadata">

**Author:** ![DNF](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dnf/32/10191_2.png) [@DNF](https://discourse.julialang.org/u/DNF)\
**Post date:** [August 4, 2022, 3:20pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-turn-off-the-warnings-indexing-with-indices-obtained-from-length-size-etc-is-discouraged-in-vscode/85093/15 "2022-08-04T15:20:46Z")

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If it is intended as a replacement for ‘ordinary’ indexing, which is apparently in high demand, where you either do  
`for i in 2:length(x)` or `for i in 2:size(x, dim)`, then the former can be replaced with `firstindex(x)+1:lastinde(x)` and the latter with `firstindex(x, dim)+1:lastinde(x, dim)`.

If you’re using CartesianIndices, you’ve already stepped outside of ‘old-fashioned Matlab style’ indexing.