How to add a folder path in your .jl script

New to Julia
8

Almost there

I myself push!() my custom package library onto LOAD_PATH in much the same way as you do in your example @sxd190026.

And, despite some of the comments that almost seem to imply otherwise, I don’t believe this is necessarily a bad technique.

In fact, I find it is one of the easiest ways to add your custom library of utilities to new Julia projects. I think the only real drawback is that it doesn’t lend itself quite as well to sharing these Julia environments with other co-workers.

LOAD_PATH

As @skleinbo said:

  • push!(LOAD_PATH, "/abs/path/to/my/package_lib") essentially adds a package library folder to Julia’s search path.
  • That means include() (file loading mechanism) is unaffected by LOAD_PATH.
  • However: using & import (package loading mechanisms) are affected by LOAD_PATH.

include() vs (using or import)

include("relative/path/to/file.jl"):

  • Loads code from file.jl.

import MyAwesomePackage:

  • Loads entire “package” MyAwesomePackage.

using MyAwesomePackage:

  • Essentially does the same as import MyAwesomePackage
  • But also makes any symbols export-ed from MyAwesomePackage directly available in the caller’s scope.

Also note that both using and import can be used with already-loaded modules (instead of packages) - but we’ll ignore that complexity for now (I don’t find it to be as useful in typical cases - or this discussion).

So what was missing?

There were really only 2 things missing from your solution:

  1. You should import your code as a package instead of loading it as a file.
    • using MyAwesomePackage – instead of – include("file_name.jl)
  2. Packages need to be wrapped in a module - end block.

So, in "/abs/path/to/my/package_lib", I suggest you create a test package:

#MySingleFilePackage.jl
module MySingleFilePackage #Module needs to match file/package name

dosomething() = println("Execute all algorithms!")

export dosomething #If you don't want people to prepend call with "MySingleFilePackage."

end #module MySingleFilePackage

And try it out in your script:

#Just try not to run push!() more than once in your scripts:
push!(LOAD_PATH, "/abs/path/to/my/package_lib")

using MySingleFilePackage
dosomething()

What if I want to create a multi-file package?

Then I suggest you follow the structure for full-blown package described by @GunnarFarneback.

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