# Is there a way to avoid allocating memory when using Chain.jl or pipeing? Technica

**URL:** <https://discourse.julialang.org/t/is-there-a-way-to-avoid-allocating-memory-when-using-chain-jl-or-pipeing-technica/57206>\
**Category:** General Usage\
**Created:** [March 15, 2021, 3:35pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-avoid-allocating-memory-when-using-chain-jl-or-pipeing-technica/57206 "2021-03-15T15:35:38Z")\
**Posts on this page:** 2\
**Page:** 1

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**Post date:** [March 15, 2021, 3:35pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-avoid-allocating-memory-when-using-chain-jl-or-pipeing-technica/57206/1 "2021-03-15T15:35:38Z")

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Is there a way to avoid allocating memory when using Chain.jl or pipeing? Technically these are type stable and can mutate the original array to avoid allocation

```julia
julia&gt; @time @chain x begin
           _ * 1
       end;
  0.002212 seconds (2 allocations: 7.629 MiB)

julia&gt; @time @chain x begin
           _ * 1
           _ * 1
       end;
  0.008802 seconds (4 allocations: 15.259 MiB)

```

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**Author:** ![jules](https://avatars.discourse-cdn.com/v4/letter/j/41988e/32.png) [@jules](https://discourse.julialang.org/u/jules)\
**Post date:** [March 16, 2021, 12:11pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-avoid-allocating-memory-when-using-chain-jl-or-pipeing-technica/57206/2 "2021-03-16T12:11:36Z")

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You could use `rmul!` to overwrite the chained array

[Linear Algebra · The Julia Language](https://docs.julialang.org/en/v1/stdlib/LinearAlgebra/#LinearAlgebra.rmul)!

```julia
@chain x begin
    rmul!(2)
end

```

Or overwrite it like this I guess. At some point you loose the benefit of chaining syntax for stuff like this

```julia
@chain x begin
   _ .*= 1
end

```