How to import custom module in julia

Question

I have a module I wrote here:

# Hello.jl module Hello     function foo         return 1     end end 

and

# Main.jl using Hello foo() 

When I run the Main module:

$ julia ./Main.jl 

I get this error:

ERROR: LoadError: ArgumentError: Hello not found in path  in require at ./loading.jl:249  in include at ./boot.jl:261  in include_from_node1 at ./loading.jl:320  in process_options at ./client.jl:280  in _start at ./client.jl:378 while loading /Main.jl, in expression starting on line 1 

Answer 1

There is a new answer to this question since the release of Julia v0.7 and v1.0 that is slightly different. I just had to do this so I figured I'd post my findings here.

As already explained in other solutions, it is necessary to include the relevant script which defines the module. However, since the custom module is not a package, it cannot be loaded as a package with the same using or import commands as could be done in older Julia versions.

So the Main.jl script would be written with a relative import like this:

include("./Hello.jl") using .Hello foo() 

I found this explained simply in Stefan Karpinski's discourse comment on a similar question. As he describes, the situation can also get more elaborate when dealing with submodules. The documentation section on module paths is also a good reference.