# How can I just use the return value from one function but without calling that function in Julia

**URL:** <https://discourse.julialang.org/t/how-can-i-just-use-the-return-value-from-one-function-but-without-calling-that-function-in-julia/98708>\
**Category:** General Usage\
**Created:** [May 11, 2023, 11:35pm UTC](https://discourse.julialang.org/t/how-can-i-just-use-the-return-value-from-one-function-but-without-calling-that-function-in-julia/98708 "2023-05-11T23:35:44Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![jianqixi](https://avatars.discourse-cdn.com/v4/letter/j/3be4f8/32.png) [@jianqixi](https://discourse.julialang.org/u/jianqixi)\
**Post date:** [May 11, 2023, 11:35pm UTC](https://discourse.julialang.org/t/how-can-i-just-use-the-return-value-from-one-function-but-without-calling-that-function-in-julia/98708/1 "2023-05-11T23:35:44Z")

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I know it maybe weird to ask this kind of question, but I am not sure Julia has this kind of way to achieve what I want. Here is one example code:

function initialize(a,b,c)  
do something  
return x  
end

function run(a,b,c)  
do something with the output from initialize, x  
end

I am wondering that could I just use the return value from initialize() function, but without calling it? The reason I don’t want to call for initialize() is because my initialize() function is very time consuming, and the run() function is within a loop, if I call the initialize() function every time, it would be very time consuming. Any suggestions would be very appreciated.

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**Author:** ![mbaz](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mbaz/32/17295_2.png) [@mbaz](https://discourse.julialang.org/u/mbaz)\
**Post date:** [May 11, 2023, 11:59pm UTC](https://discourse.julialang.org/t/how-can-i-just-use-the-return-value-from-one-function-but-without-calling-that-function-in-julia/98708/2 "2023-05-11T23:59:38Z")

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Can you calculate `x` once and then pass it to `run`? Something like:

```julia
function initialize(a, b, c)
    ...
end

function run(a, b, c, x)
    ...
end

x = initialize(a, b, c)

for ...
   run(a, b, c, x)
end

```

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**Author:** ![Keno](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/keno/32/285_2.png) [@Keno](https://discourse.julialang.org/u/Keno)\
**Post date:** [May 12, 2023, 12:10am UTC](https://discourse.julialang.org/t/how-can-i-just-use-the-return-value-from-one-function-but-without-calling-that-function-in-julia/98708/3 "2023-05-12T00:10:46Z")

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Are you looking for memoization? [GitHub - JuliaCollections/Memoize.jl: ＠memoize macro for Julia](https://github.com/JuliaCollections/Memoize.jl)