工作流程建议

这里是高效使用 Julia 的一些建议。

基于 REPL 的工作流程

正如在 Julia REPL 中演示的那样，Julia 的 REPL 为高效的交互式工作流程提供了丰富的功能。这里是一些可能进一步提升你在命令行下的体验的建议。

一个基本的编辑器 / REPL 工作流程

最基本的 Julia 工作流程是将一个文本编辑器配合 julia 的命令行使用。一般会包含下面一些步骤：

  • 把还在开发中的代码放到一个临时的模块中。新建一个文件，例如 Tmp.jl，并放到模块中。

    1. module Tmp
    2. export say_hello
    4. say_hello() = println("Hello!")
    6. # your other definitions here
    8. end

  • 把测试代码放到另一个文件中。新建另一个文件，例如 tst.jl，开头为

    1. include("Tmp.jl")
    2. import .Tmp
    3. # using .Tmp # we can use `using` to bring the exported symbols in `Tmp` into our namespace
    5. Tmp.say_hello()
    6. # say_hello()
    8. # your other test code here

    并把测试作为 Tmp 的内容。或者，你可以把测试文件的内容打包到一个模块中，例如

    1. module Tst
    2.     include("Tmp.jl")
    3.     import .Tmp
    4.     #using .Tmp
    6.     Tmp.say_hello()
    7.     # say_hello()
    9.     # your other test code here
    10. end

    优点是你的测试代码现在包含在一个模块中，并且不会在 Main 的全局作用域中引入新定义，这样更加整洁。

  • 使用 include("tst.jl") 来在 Julia REPL 中 include tst.jl 文件。

  • 打肥皂，冲洗，重复。（译者注：此为英语幽默，被称为“洗发算法”在 julia REPL 中摸索不同的想法，把好的想法存入 tst.jl。要在 tst.jl 被更改后执行它，只需再次 include 它。

基于浏览器的工作流程

也可以通过 IJulia 在浏览器中与 Julia REPL 进行交互，请到该库的主页查看详细用法。

Revise-based workflows

Whether you’re at the REPL or in IJulia, you can typically improve your development experience with Revise. It is common to configure Revise to start whenever julia is started, as per the instructions in the Revise documentation. Once configured, Revise will track changes to files in any loaded modules, and to any files loaded in to the REPL with includet (but not with plain include); you can then edit the files and the changes take effect without restarting your julia session. A standard workflow is similar to the REPL-based workflow above, with the following modifications:

  1. Put your code in a module somewhere on your load path. There are several options for achieving this, of which two recommended choices are:

    a. For long-term projects, use PkgTemplates:

    julia using PkgTemplates t = Template() generate("MyPkg", t) This will create a blank package, "MyPkg", in your .julia/dev directory. Note that PkgTemplates allows you to control many different options through its Template constructor.

    In step 2 below, edit MyPkg/src/MyPkg.jl to change the source code, and MyPkg/test/runtests.jl for the tests.

    b. For “throw-away” projects, you can avoid any need for cleanup by doing your work in your temporary directory (e.g., /tmp).

    Navigate to your temporary directory and launch Julia, then do the following:

    julia pkg> generate MyPkg # type ] to enter pkg mode julia> push!(LOAD_PATH, pwd()) # hit backspace to exit pkg mode If you restart your Julia session you’ll have to re-issue that command modifying LOAD_PATH.

    In step 2 below, edit MyPkg/src/MyPkg.jl to change the source code, and create any test file of your choosing.

  2. Develop your package

    Before loading any code, make sure you’re running Revise: say using Revise or follow its documentation on configuring it to run automatically.

    Then navigate to the directory containing your test file (here assumed to be "runtests.jl") and do the following:

    1. julia> using MyPkg
    3. julia> include("runtests.jl")

    You can iteratively modify the code in MyPkg in your editor and re-run the tests with include("runtests.jl"). You generally should not need to restart your Julia session to see the changes take effect (subject to a few limitations, see https://timholy.github.io/Revise.jl/stable/limitations/).