# Importing modules from function

**URL:** <https://discourse.julialang.org/t/importing-modules-from-function/24834>\
**Category:** General Usage\
**Created:** [June 1, 2019, 11:18am UTC](https://discourse.julialang.org/t/importing-modules-from-function/24834 "2019-06-01T11:18:50Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![oli](https://avatars.discourse-cdn.com/v4/letter/o/2bfe46/32.png) [@oli](https://discourse.julialang.org/u/oli)\
**Post date:** [June 1, 2019, 11:18am UTC](https://discourse.julialang.org/t/importing-modules-from-function/24834/1 "2019-06-01T11:18:50Z")

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Hi,

I’m working on a project at the moment that involves many packages and modules, as well as many different files. I have a “setup.jl” file that adds all the packages (`Pkg.add("Pkg_name"); using Pkg_name;`) and includes all the files (`include("./filename")`). That way, I can simply start Julia and run the command `include("setup.jl")` and I can use all of the code.

I however don’t like how I import packages. Essentially, I am using a try-catch system, where I try `using Pkg_name` and the catch is `Pkg.add("Pkg_name"); using Pkg_name`. I would like to call a function which would do that for me. That way, I wouldn’t have to write the try-catch for every package and I could simply write a for loop that goes through all the packages and imports them. The problem is with “using” because it uses a package identifier and I’m not sure how to convert a string (the package name) into a package identifier. I tried `using $Pkg_name`, as well as `using Symbol(Pkg_name)` but both do not work. Here is what I have in mind in a nutshell:

```julia-auto
# Function to import packages
function use_pkg( pkg_name )
    try
        using pkg_name;
    catch err;
        Pkg.add("pkg_name");
        using pkg_name;
    end
end

# Defining list of packages to import
pkg_list = ["CSV", "Random", "Plots"]; # There would be more packages of course

# Importing all packages
for i = 1:length( pkg_list )
    if !in( pkg_list[i], keys( Pkg.installed( ) ) )
        use_pkg( pkg_list[i] );
    end
end

```

Does anyone have any idea on how to do this?

## Debug info

Julia Version 1.0.0  
Commit 5d4eaca0c9 (2018-08-08 20:58 UTC)  
Platform Info:  
OS: Windows (x86\_64-w64-mingw32)  
CPU: Intel(R) Core™ i7-4710HQ CPU @ 2.50GHz  
WORD\_SIZE: 64  
LIBM: libopenlibm  
LLVM: libLLVM-6.0.0 (ORCJIT, haswell)

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<div class="post-metadata">

**Author:** ![c42f](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/c42f/32/52842_2.png) [@c42f](https://discourse.julialang.org/u/c42f)\
**Post date:** [June 1, 2019, 11:48am UTC](https://discourse.julialang.org/t/importing-modules-from-function/24834/2 "2019-06-01T11:48:50Z")

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As you’ve found, you can’t quite do it this way because `using` is forbidden inside functions. Instead it’s limited to top level so that the compiler can generate efficient function code without having to worry that new functions will be added while a function is running. There’s ways to do what you’re imagining in this particular case by hacking around this design feature.

However, if you just want a nice way to make sure that all packages are installed in your project it’s much better to use `Pkg` itself which has builtin support for creating environments with a well defined set of packages. Here’s the documentation: [4. Working with Environments · Pkg.jl](https://julialang.github.io/Pkg.jl/v1/environments/#Creating-your-own-projects-1)

Once you’ve set up an environment for your project I suggest you add Project.toml to your source control and start julia with the `--project=$project_dir`. See [what is `@.` in Julia `--project` command line option? - Stack Overflow](https://stackoverflow.com/questions/53613663/what-is-in-julia-project-command-line-option) for a nice explanation of `--project`.

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<div class="post-metadata">

**Author:** ![oli](https://avatars.discourse-cdn.com/v4/letter/o/2bfe46/32.png) [@oli](https://discourse.julialang.org/u/oli)\
**Post date:** [June 1, 2019, 12:05pm UTC](https://discourse.julialang.org/t/importing-modules-from-function/24834/3 "2019-06-01T12:05:37Z")

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Awesome! Thanks for the quick response. I’ll take a look at that 🙂