# Iterators.cat?

**URL:** <https://discourse.julialang.org/t/iterators-cat/43399>\
**Category:** Internals & Design\
**Created:** [July 20, 2020, 7:36pm UTC](https://discourse.julialang.org/t/iterators-cat/43399 "2020-07-20T19:36:27Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![CameronBieganek](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cameronbieganek/32/6915_2.png) [@CameronBieganek](https://discourse.julialang.org/u/CameronBieganek)\
**Post date:** [July 20, 2020, 7:36pm UTC](https://discourse.julialang.org/t/iterators-cat/43399/1 "2020-07-20T19:36:27Z")

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Is there any appetite for an `Iterators.cat` function? I often use `Iterators.flatten` like this:

```julia
Iterators.flatten((itr1, itr2, itr3))

```

But it feels kind of silly to put the iterators in a tuple just so I can concatenate them. I think a more natural syntax would be

```julia
Iterators.cat(itr1, itr2, itr3)

```

where `Iterators.cat` is a `Vararg` function.

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<div class="post-metadata">

**Author:** ![StefanKarpinski](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/stefankarpinski/32/24_2.png) [@StefanKarpinski](https://discourse.julialang.org/u/StefanKarpinski)\
**Post date:** [July 21, 2020, 4:47pm UTC](https://discourse.julialang.org/t/iterators-cat/43399/2 "2020-07-21T16:47:36Z")

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Seems worth opening an issue to discuss.

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<div class="post-metadata">

**Author:** ![CameronBieganek](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cameronbieganek/32/6915_2.png) [@CameronBieganek](https://discourse.julialang.org/u/CameronBieganek)\
**Post date:** [July 22, 2020, 4:28am UTC](https://discourse.julialang.org/t/iterators-cat/43399/3 "2020-07-22T04:28:07Z")

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Ok, I created an issue:

[https://github.com/JuliaLang/julia/issues/36760](https://github.com/JuliaLang/julia/issues/36760)

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<div class="post-metadata">

**Author:** ![nsajko](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nsajko/32/221187_2.png) [@nsajko](https://discourse.julialang.org/u/nsajko)\
**Post date:** [February 8, 2026, 10:04pm UTC](https://discourse.julialang.org/t/iterators-cat/43399/4 "2026-02-08T22:04:08Z")

</div>

PR:

> <https://github.com/JuliaLang/julia/pull/60965>
>
> I feel it is common to want to concatenate several iterators. While the implemen…tation is extremely simple, the approach is not completely obvious. A newcomer, especially, might choose to use the more verbose \`Iterators.flatten((i, j))\` instead of cooking up their own \`Iterators.cat\`.
> 
> Fixes #36760