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:
I have a folder called Script_py, and containing a lot of .py files, for example tri_insertion.py and tri_rapide.py.
Each name.py contains just one function called also name. My aim is to :
import all the functions (and if I have to add an other .py file, it will be imported automatically),
execute one function with the command 'name(parameters)'.
I tried the solutions of How to load all modules in a folder? with a dynamic ___all___ in ___init___.py, and from Script_py import all, but a calling to a function is name.name(parameters) instead of name(parameters)
Finally the following solution works fine. Fristly, I store in a list the complete list of modules :
import os, pkgutil
test = list(module for _, module, _ in
pkgutil.iter_modules([os.path.dirname('absolute_path')]))
Secondly, I import all the modules with a for loop.
for script in test:
exec("from {module} import *".format(module=script))
I am receiving this warning message in my chrome console for my react-native project. Do you have any idea why I am getting this?
This is the complete message:
Require cycle: node_modules/react-native-radio-buttons/lib/index.js ->
node_modules/react-native-radio-buttons/lib/segmented-controls.js ->
node_modules/react-native-radio-buttons/lib/index.js
Require cycles are allowed, but can result in uninitialized values.
Consider refactoring to remove the need for a cycle.
I appreciate any suggestions.
Thanks
TL;DR: You import module A into module B and module B into module A resulting in a cycle A → B → A → B → A ..., which can result in errors. Resolve that by restructuring your modules, so that the cycle breaks.
Detailed Answer
In javascript if you import different modules into other modules all this importing generates a dependency tree:
root_module
┌───────────┴───────────┐
sub_module_A sub_module_B
┌────────┴────────┐
sub_module_C sub_module_D
When you run your code, all modules will be evaluated from bottom to top or from leaves to the trunk, so that for example if you import modules C and D into module B all exports of C and D are already evaluated and not undefined anymore. If module B would be evaluated before C and D, module B would be not working, because all exports from C and D would be undefined, since they have not been evaluated yet.
Still, it can be possible to form cycles in your dependency tree (this is what you got a warning for):
root_module
┌───────────┴───────────┐
sub_module_A sub_module_B
↑ ↓
sub_module_C
Problem: Let's say the evaluation starts now with module C. Since it imports something from module B and it has not been evaluated yet, module C is not working correctly. All imported stuff from B is undefined. This actually is not that bad, since in the end module C is evaluated once again when everything else has been evaluated, so that also C is working. The same goes if evaluation starts with module B.
BUT: If your code relies on a working module C from the very beginning, this will result in very hard to find errors. Therefore you get this error.
How to solve: In your case the warning also gives a detailed explanation, where the cycle emerges. You import native-radio-buttons/lib/segmented-controls.js in node_modules/react-native-radio-buttons/lib/index.js and node_modules/react-native-radio-buttons/lib/index.js in native-radio-buttons/lib/segmented-controls.js. It seems like the cycle is placed inside some of your node modules. In this case there is unfortunately no way you could solve that by yourself.
If the cycle is in your own code, you have to extract some exports into a third module / file, from which you import the code into both modules previously forming the cycle.
You are probably importing something from "file A" into "file B", then importing something again from "file B" into "file A" .
Examine all the imports from both the files and see if there's any such cycle.
To prevent from having to write multiple lines of
import SomeComponent from "../components"
import AnotherComponent from "../components"
import AndAnotherComponent from "../components"
import AndOneMoreComponent from "../components"
I created a comp.js file where I could import the components as they are created and export them as modules.
All components are then able to be reached from one place.
So you can then have something like this in some place...
import { SomeComponent, AnotherComponent, AndAnotherComponent, AndOneMoreComponent} from './comp'
Now what happens in the renderer for example when SomeComponent is rendered....
import * as React from "react";
import { AnotherComponent} from '../comps';
import { View, Text } from "react-native";
function SomeComponent() {
return (
<>
<AnotherComponent />
<View><Text>EXAMPLE OF SOMECOMPONENT</Text></View>
</>
)
}
export default SomeComponent;
In the example, SomeComponent could be called in the main App, and when it renders it also asks for a component from the comp.js
This is what triggers the Require cycle warning because a module that was imported from one place, is then rendering and asking to import another module from the same place it was rendered from.
What are your thoughts on this, should I revert back to using single import statements or do you think there is a danger in using the module export as it is currently setup?
I my case, I have sold the same problem in react-native navgiation.
What I did ?
Already I was using react-navigation like below
export const containerRef = createRef();
function App(){
return (
<NavigationContainer ref={containerRef}>
....
<NavigationContainer>
);
}
and then I was consuming it like:
import {containerRef} from 'filename';
onPress = ()=> containerRef.current.navigate('Chat');
But I updated like below and warning has gone.
function App(){
return (
<NavigationContainer> // removed ref
....
<NavigationContainer>
);
}
and then I was consuming it like:
import { useNavigation } from '#react-navigation/native';
onPress = ()=> useNavigation.navigate('Chat');
This occurs if your code contains cyclic dependencies. If these dependencies exist within your own libraries, you can easily fix them. But if this is happening in 3rd party libraries, you can't do much except waiting for the developers to fix these.
Another reason might be this: Some imports cause this warning if they're done through the require keyword. Replace these with import statements and you might be good to go. For example,
const abc = require("example"); // Don't use this syntax
import abc from "example" // Use this syntax instead
NOTE: This might vary from project to project. For a detailed understanding of require vs import, refer to this link.
In my case the warning was like this;
Require cycle: src\views\TeamVerification.js -> src\components\TeamVerificationListItem.js ->
src\views\TeamVerification.js Require cycles are allowed, but can result in uninitialized values. Consider refactoring to remove the need for a cycle.
As it indicates, TeamVerification was importing TeamVerificationListItem and TeamVerificationListItem was also importing TeamVerification. It was an unused import but after I remove it the warning gone.
As others have already mentioned, for your own packages
Move things required within two modules by each other into a third module
Avoid imports from barrel-files (index.ts/js) or aliases (#mycompany/my-module) if you are within the same "my-module"
What others have not mentioned (and which seems to be the problem for OP), for packages not within your responsibility (eg node_modules from NPM), the only thing you can do is
Disable the warning. It will still show up in metro console, but no more yellow warning snackbar: import { LogBox } from 'react-native'; LogBox.ignoreLogs(['Require cycle: node_modules/']); You can place the code in App.tsx, for example.
Modify the package contents of the node_modules itself and patch the package contents after every npm install via patch-package => I think this is an overkill if the circular imports don't produce actual errors
You should use the Relation wrapper type in relation properties in ES Modules projects to avoid circular dependency issues, just click here: https://typeorm.io/#relations-in-esm-projects
In my case, i had the same warning after the installation of a 'package'
and in their documentation, it was import SomeFunc from 'package'
and instantly the warning showed up
Require cycles are allowed but can result in uninitialized values. Consider refactoring to remove the need for a cycle.
but as soon as I destructure the SomeFunc there was no more warning
import {SomeFunc} from 'package'
please look at the destructuring
I used react-native-maps in my project and I got the same error.
Just upgraded from 0.27.1 -> 0.28.0.
I can confirm that this issue is fixed.
Thank you
if use NavigationContainer in #react-navigation/native
import {createRef} from 'react';
<NavigationContainer ref={createRef()}>
Please check whether you have imported same details within that file.
(i.e)
your file being as a actions/meals.js and you have added the line in the same file like
import { Something } from './actions/meals.js'
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.
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?