From a module, consult a file in another module - module

For some reason, in my Prolog module I want to be able to consult a file, but like if it was consulted from another module (e.g. user).
Say I have a file named myfile.pl containing:
foo(1).
Normally, if in module mymodule I execute consult(myfile), what I have is a new predicate mymodule:foo/1.
I would like to be able to consult the file from module mymodule but the resulting predicate be like user:foo/1.
Is this possible?

Did you tried to call consult(user:myfile) from within your mymodule module?

Related

Python.Net: how to execute modules in packages?

I'm not a Python programmer so apologies if I don't get some of the terminology right (pacakages, modules)!
I have a folder structure that looks something like this:
C:\Test\System\
C:\Test\System\intercepts\
C:\Test\System\intercepts\utils1\
C:\Test\System\intercepts\utils2\
The last three folders each contain an empty __init__.py folder, while the latter two folders (\utils1, \utils2) contain numerous .py modules. For the purposes of my question I'm trying to execute a function within a module called "general.py" that resides in the \utils1 folder.
The first folder (C:\Test\System) contains a file called "entry.py", which imports the .py modules from all those sub-folders:
from intercepts.utils1 import general
from intercepts.utils1 import foobar
from intercepts.utils2 import ...
..etc..
And here is the C# code that executes the above module then attempts to call a function called "startup" in a module called "general.py" in the \utils1 folder:
const string EntryModule = #"C:\Test\System\entry.py";
using (Py.GIL())
{
using (var scope = Py.CreateScope())
{
var code = File.ReadAllText(EntryModule);
var scriptCompiled = PythonEngine.Compile(code, EntryModule);
scope.Execute(scriptCompiled);
dynamic func = scope.Get("general.startup");
func();
}
}
However I get a PythonException on the scope.Execute(...) line, with the following message:
No module named 'intercepts'
File "C:\Test\System\entry.py", line 1, in <module>
from intercepts.utils1 import general
I'm able to do the equivalent of this using IronPython (Python 2.7), so I assume I'm doing something wrong with Python.Net (rather than changes to how packages work in Python 3.x).
I'm using the pythonnet 3.0.0 NuGet package by the way.
Edit
I've tried importing my "entry.py" module as follows:
dynamic os = Py.Import("os");
dynamic sys = Py.Import("sys");
sys.path.append(os.path.dirname(EntryModule));
Py.Import(Path.GetFileNameWithoutExtension(EntryModule));
It now appears to get a little further, however there's a new problem:
In the "entry.py" module you can see that it first imports a module called "general", then a module called "foobar". "foobar.py" contains the line import general.
When I run my C#, the stack trace is now as follows:
No module named 'general'
File "C:\Test\System\intercepts\utils1\foobar.py", line 1, in <module>
import general
File "C:\Test\System\entry.py", line 2, in <module>
from intercepts.utils1 import foobar
Why can't the second imported module ("foobar") "see" the module that was imported immediately before it ("general")? Am I even barking up the right tree by using Py.Import() to solve my original issue?
This turned out to be a change in how Python 3 handles imports, compared to 2, and nothing to do with Python.Net.
In my "foobar.py" module I had to change import general to from . import general. The issue is explained here but I've included the pertinent section below:

Creating and using a custom module in Julia

Although this question has been asked before, it appears that much has changed with respect to modules in Julia V1.0.
I'm trying to write a custom module and do some testing on it. From the Julia documentation on Pkg, using the dev command, there is a way to create a git tree and start working.
However, this seems like overkill at this point. I would like to just do a small local file, say mymodule.jl that would be like:
module MyModule
export f, mystruct
function f()
end
struct mystruct
x::Integer
end
end # MyModule
It appears that it used to be possible to load it with
include("module.jl")
using MyModule
entering the include("module.jl"), it appears that the code loads, i.e. there is no error, however, using MyModule gives the error:
ArgumentError: Package MyModule not found in current path:
- Run `import Pkg; Pkg.add("MyModule")` to install the MyModule package.
I notice that upon using include("module.jl"), there is access to the exported function and struct using the full path, MyModule.f() but I would like the shorter version, just f().
My question then is: to develop a module, do I need to use the Pkg dev command or is there a lighter weight way to do this?
In order to use a local module, you must prefix the module name with a ..
using .MyModule
When using MyModule is run (without the .), Julia attempts to find a module called MyModule installed to the current Pkg environment, hence the error.

How to use words from a named module inside another?

I'm looking for an example of how to use words exported from a named module inside another module.
From the help of import
REFINEMENTS:
/version
ver [tuple!]
Module must be this version or greater
/check
sum [binary!]
Match checksum (must be set in header)
/no-share
Force module to use its own non-shared global namespace
/no-lib
Don't export to the runtime library (lib)
/no-user
Don't export to the user context
it would suggest that import/no-lib doesn't place the imported word in the lib context, so import by itself should? But it doesn't.
This works but it seems that import by itself should work.
import/no-lib %my-named-module.reb
append lib compose [f: (:my-exported-function))
and I can then access the function by using lib/f
;in module1
word1: ...
;in module2
mod1: import 'module1
word1: :mod1/word1

Powershell v2 - The correct way to load an assembly as part of a module

I have a Powershell (v2.0) script that I am working on.
One of the first things it does is loads a Module (runMySQLQuery.psm1) which includes (amongst other bits) a function to connect to a MySQL Database.
Import-Module runMySQLQuery.psm1
However, this requires that an assembly MySQL.Data.DLL is loaded in order for this to work.
If I place the line:
[void][system.reflection.Assembly]::LoadFrom("C:\PowerShell\modules\runMySQLQuery\MySql.Data.dll")
at the top of my script (separate to the Import-Module entry), then the whole thing works fine.
But I want to be able to load this assembly at the same time as the module, so that I don't have to worry about forgetting to including the assembly each time I use this module.
I tried placing it at the top of the .psm1 file, but that didn't work.
I then added it to my manifest file as:
RequiredAssemblies = #("C:\PowerShell\modules\runMySQLQuery\MySql.Data.dll")
This also didn't work.
Am I missing something here, is there a proper way to include assemblies as part of a module?
n.b. the error I get when it hasn't loaded properly is:
You cannot call a method on a null-valued expression
Can you just try to assign a varialbe a the beginig of you module :
$dumy = [system.reflection.Assembly]::LoadFrom("C:\PowerShell\modules\runMySQLQuery\MySql.Data.dll")

How do I reload a module in an active Julia session after an edit?

2018 Update: Be sure to check all the responses, as the answer to this question has changed multiple times over the years. At the time of this update, the Revise.jl answer is probably the best solution.
I have a file "/SomeAbsolutePath/ctbTestModule.jl", the contents of which are:
module ctbTestModule
export f1
f1(x) = x + 1
end
I fire up Julia in a terminal, which runs "~/.juliarc.jl". The startup code includes the line:
push!(LOAD_PATH, "/SomeAbsolutePath/")
Hence I can immediately type into the Julia console:
using ctbTestModule
to load my module. As expected f1(1) returns 2. Now I suddenly decide I want to edit f1. I open up "/SomeAbsolutePath/ctbTestModule.jl" in an editor, and change the contents to:
module ctbTestModule
export f1
f1(x) = x + 2
end
I now try to reload the module in my active Julia session. I try
using ctbTestModule
but f1(1) still returns 2. Next I try:
reload("ctbTestModule")
as suggested here, but f1(1) still returns 2. Finally, I try:
include("/SomeAbsolutePath/ctbTestModule.jl")
as suggested here, which is not ideal since I have to type out the full absolute path since the current directory might not be "/SomeAbsolutePath". I get the warning message Warning: replacing module ctbTestModule which sounds promising, but f1(1) still returns 2.
If I close the current Julia session, start a new one, and type in using ctbTestModule, I now get the desired behaviour, i.e. f1(1) returns 3. But obviously I want to do this without re-starting Julia.
So, what am I doing wrong?
Other details: Julia v0.2 on Ubuntu 14.04.
The basis of this problem is the confluence of reloading a module, but not being able to redefine a thing in the module Main (see the documentation here) -- that is at least until the new function workspace() was made available on July 13 2014. Recent versions of the 0.3 pre-release should have it.
Before workspace()
Consider the following simplistic module
module TstMod
export f
function f()
return 1
end
end
Then use it....
julia> using TstMod
julia> f()
1
If the function f() is changed to return 2 and the module is reloaded, f is in fact updated. But not redefined in module Main.
julia> reload("TstMod")
Warning: replacing module TstMod
julia> TstMod.f()
2
julia> f()
1
The following warnings make the problem clear
julia> using TstMod
Warning: using TstMod.f in module Main conflicts with an existing identifier.
julia> using TstMod.f
Warning: ignoring conflicting import of TstMod.f into Main
Using workspace()
However, the new function workspace() clears Main preparing it for reloading TstMod
julia> workspace()
julia> reload("TstMod")
julia> using TstMod
julia> f()
2
Also, the previous Main is stored as LastMain
julia> whos()
Base Module
Core Module
LastMain Module
Main Module
TstMod Module
ans Nothing
julia> LastMain.f()
1
Use the package Revise, e.g.
Pkg.add("Revise") # do this only once
include("src/my_module.jl")
using Revise
import my_module
You may need to start this in a new REPL session. Notice the use of import instead of using, because using does not redefine the function in the Main module (as explained by #Maciek Leks and #waTeim).
Other solutions: Two advantages of Revise.jl compared to workspace() are that (1) it is much faster, and (2) it is future-proof, as workspace() was deprecated in 0.7, as discussed in this GitHub issue:
julia> VERSION
v"0.7.0-DEV.3089"
julia> workspace()
ERROR: UndefVarError: workspace not defined
and a GitHub contributor recommended Revise.jl:
Should we add some mesage like "workspace is deprecated, check out Revise.jl instead"?
Even in Julia 0.6.3, the three previous solutions of workspace(), import, and reload fail when a module called other modules, such as DataFrames. With all three methods, I got the same error when I called that module the second time in the same REPL:
ERROR: LoadError: MethodError: all(::DataFrames.##58#59, ::Array{Any,1}) is ambiguous. Candidates: ...
I also got many warning messages such as:
WARNING: Method definition macroexpand(Module, ANY) in module Compat at /Users/mmorin/.julia/v0.6/Compat/src/Compat.jl:87 overwritten in module Compat at /Users/mmorin/.julia/v0.6/Compat/src/Compat.jl:87.
Restarting the Julia session worked, but it was cumbersome. I found this issue in the Reexport package, with a similar error message:
MethodError: all(::Reexport.##2#6, ::Array{Any,1}) is ambiguous.
and followed the suggestion of one contributor:
Does this happen without using workspace()? That function is notorious for interacting poorly with packages, which is partly why it was deprecated in 0.7.
In my humble opinion, the better way is to use import from the very beginning instead of using for the reported issue.
Consider the module:
module ModuleX1
export produce_text
produce_text() = begin
println("v1.0")
end
println("v1.0 loaded")
end
Then in REPL:
julia> import ModuleX1
v1.0 loaded
julia> ModuleX1.produce_text()
v1.0
Update the code of the module and save it:
module ModuleX1
export produce_text
produce_text() = begin
println("v2.0")
end
println("v2.0 loaded")
end
Next, in the REPL:
julia> reload("ModuleX1")
Warning: replacing module ModuleX1
v2.0 loaded
julia> ModuleX1.produce_text()
v2.0
Advantages of using import over using:
avoiding ambiguity in function calls (What to call: ModuleX1.produce_text() or produce_text() after reloading?)
do not have to call workspace() in order to get rid of ambiguity
Disadvantages of using import over using:
a fully qualified name in every call for every exported name is needed
Edited: Discarded "full access to the module, even to the not-exported names" from "Disadvantages..." according to the conversation below.
workspace() has been deprecated.
You can reload("MyModule") in an active REPL session, and it works as expected: changes made to the source file that contains MyModule are reflected in the active REPL session.
This applies to modules that have been brought into scope by either import MyModule or using MyModule
I wanted to create a new module from scratch, and tried the different answers with 1.0 and didn’t get a satisfactory result, but I found the following worked for me:
From the Julia REPL in the directory I want to use for my project I run
pkg> generate MyModule
This creates a subdirectory like the following structure:
MyModule
├── Project.toml
└── src
└── MyModule.jl
I put my module code in MyModule.jl. I change to the directory MyModule (or open it in my IDE) and add a file Scratch.jl with the following code:
using Pkg
Pkg.activate(".")
using Revise
import MyModule # or using MyModule
Then I can add my code to test below and everything updates without reloading the REPL.
I battled to get Revise.jl to work for me, probably because I also use code generation with OOPMacro #class . I had to also call revise(...) See https://timholy.github.io/Revise.jl/stable/limitations/#Limitations-1.
I have been struggling with this problem for up to 5 years and finally got something that works for me that don't involve manually running my main module in the IDE repl after EVERY SMALL CHANGE :'(
Here is some of my code I use to force a revise and exit early when running tests when there were revise errors:
# Common code I include into my test files now:
using Pkg
using Revise
# force include module
Pkg.activate("MyModule")
include("../src/MyModule.jl")
Pkg.activate("MyModule/test")
using Revise
# if there were any revise errors which means some compilation error or
# some change that requires a manual rerun or restart.
# then force you to fix it, rather that running lying tests..
for (k, e) in Revise.queue_errors
if !isnothing(e)
warn(logger, "Something went wrong while revising, you probably have a compile error in this file:")
throw(e)
end
end
module TestSomethingModule
using Revise
using MyModule
revise(MyModule)
...
# then you can call MyModule.doSomithing in a test and it actually updates
end