Workflow Tips

# Workflow Tips

Here are some tips for working with Julia efficiently.

## REPL-based workflow

As already elaborated in Interacting With Julia, Julia's REPL provides rich functionality that facilitates an efficient interactive workflow. Here are some tips that might further enhance your experience at the command line.

### A basic editor/REPL workflow

The most basic Julia workflows involve using a text editor in conjunction with the `julia` command line. A common pattern includes the following elements:

- Put code under development in a temporary module. Create a file, say `Tmp.jl`, and include within it

      module Tmp

      <your definitions here>

      end

- Put your test code in another file. Create another file, say `tst.jl`, which begins with

      import Tmp

  and includes tests for the contents of `Tmp`. The value of using `import` versus `using` is that you can call `reload("Tmp")` instead of having to restart the REPL when your definitions change. Of course, the cost is the need to prepend `Tmp.` to uses of names defined in your module. (You can lower that cost by keeping your module name short.)

  Alternatively, you can wrap the contents of your test file in a module, as

      module Tst
          using Tmp

          <scratch work>

      end

  The advantage is that you can now do `using Tmp` in your test code and can therefore avoid prepending `Tmp.` everywhere. The disadvantage is that code can no longer be selectively copied to the REPL without some tweaking.

- Lather. Rinse. Repeat. Explore ideas at the `julia` command prompt. Save good ideas in `tst.jl`. Occasionally restart the REPL, issuing

      reload("Tmp")
      include("tst.jl")

### Simplify initialization

To simplify restarting the REPL, put project-specific initialization code in a file, say `_init.jl`, which you can run on startup by issuing the command:

    julia -L _init.jl

If you further add the following to your `.juliarc.jl` file

    isfile("_init.jl") && include(joinpath(pwd(), "_init.jl"))

then calling `julia` from that directory will run the initialization code without the additional command line argument.

## Browser-based workflow

It is also possible to interact with a Julia REPL in the browser via IJulia. See the package home for details.