circular-dependency | 易学教程

Remove python circular import

阅读更多关于 Remove python circular import

问题 user.py: from story import Story class User: ... def get_stories(self): story_ids = [select from database] return [Story.get_by_id(id) for id in story_ids] story.py from user import User class Story: ... def __init__(self, id, user_id, content): self.id = id self.user = User.get_by_id(user_id) self.content = content as you can see, there is a circular import in this program, which causes an ImportError . I learned that I can move the import statement in method definition to prevent this error

Getting around circular reference in Google Spreadsheet

阅读更多关于 Getting around circular reference in Google Spreadsheet

问题 I have a google docs spreadsheet with two columns: A and B. Values of B are just values from A in a different format, and I have a formula in the B column that does the conversion. Sometimes I do not have the values in A format but I have them in B format. I would like to automatically get the values in A format in the A column by adding the formula that does the reverse conversion in the A column. This, of course, generates a circular reference. Is there a way to get around it? 回答1: From

Fortran OOP circular dependency handling, interfaces

阅读更多关于 Fortran OOP circular dependency handling, interfaces

Compiler: ifort version 12.1.5 I'm writing some Fortran code and I'd like to make use of some F2003 OOP features, but I'm hitting some stumbling blocks. Paring down the example, I wish to have two derived types A and B, each of which have a pointer to instances of the other. In Fortran, circular dependencies between modules are explicitly disallowed, so these two types would have to reside in the same module. This compiles: module testModule implicit none type A type(B),pointer :: b1 end type A type B type(A),pointer :: a1 end type B contains [some possibly type-bound procedures] end module

boost::shared_ptr cycle break with weak_ptr

阅读更多关于 boost::shared_ptr cycle break with weak_ptr

I am currently in a situation like: struct A { shared_ptr<B> b; }; struct B { shared_ptr<A> a; }; //... shared_ptr<A> a(new A()); shared_ptr<B> b(new B()); a->b(b); b->a(a); I know this won't work, because the references would continue to point to each other. I've also been told that weak_ptr solves this issue. However, weak_ptr has no get or -> overload. I've heard mentions of 'use lock() ', but can anyone give code examples of how to do this correctly? Come on now. http://boost.org/doc/libs/1_42_0/libs/smart_ptr/weak_ptr.htm ^^^^^ EXAMPLE IS RIGHT THERE ^^^^^^ DAMN! I think the bigger issue

How to handle circularly dependent observables in RxJS?

阅读更多关于 How to handle circularly dependent observables in RxJS?

问题 Let's say e.g. that somewhere on a server there is a mapping between integers and names and a web page provides a simple input where a user can enter a number and is given the corresponding name. In its basic form, this problem is simple: const input$ = Rx.Observable.fromEvent(..., "input"); const request$ = input$.map( ... ); const serverResponse$ = request$.flatMap( askServer ); Now I would like to cache the results so that a request is only done when the number is not in the cache. const

Gson Serialize Circular References Using Stubs

阅读更多关于 Gson Serialize Circular References Using Stubs

I'm trying to implement some simple Json serialization functionality but I'm having a hard time coping with the massive complexity of Gson. So basically I have a bunch of Entity classes which reference each other with a lot of circular reference. To serialize this structure to JSON I want to keep track of the objects already serialized. The Entity classes all implement an interface called Identified which has one method String getId() giving a globally unique id. So during serializiation of one root element, I want to store all encountered ids in a Set and decide based on that set, whether to

ES6 Modules and Circular Dependency

阅读更多关于 ES6 Modules and Circular Dependency

I'm having this problem in ES6 in a Babel Environment: // A.js class A { } export default new A(); // B.js import C from './C'; class B { } export default new B(); // C.js import A from './A'; import B from './B'; class C { constructor(A, B){ this.A = A; this.B = B; // undefined } } export default new C(A, B) I import them like this: // stores/index.js import A from './A'; import B from './B'; import C from './C'; export { A, B, C } And from my app entry point I do: import * as stores from './stores'; I would (hoped) expected the order of execution to be A -> B ->C but in reality it is A-> C->

Best practice for structuring module exceptions in Python3

阅读更多关于 Best practice for structuring module exceptions in Python3

问题 Suppose I have a project with a folder structure like so. /project __init__.py main.py /__helpers __init__.py helpers.py ... The module helpers.py defines some exception and contains some method that raises that exception. # /project/__helpers/helpers.py class HelperException(Exception): pass def some_function_that_raises(): raise HelperException On the other hand my main.py module defines its own exceptions and imports methods that may raise an exception from helpers.py . # /projects/main.py

Calling IMappingEngine.Map inside custom mapping

阅读更多关于 Calling IMappingEngine.Map inside custom mapping

问题 With AutoMapper, when using ConvertUsing to define a custom mapping for a type that is a container, I often need to call IMappingEngine.Map inside the mapping function. This is necessary because it allows-me to reuse the definition of the child mapping. CreateMap<Order, OrderModel>() .ConvertUsing(o => new OrderModel( o.Id, o.ShippingAddress, mapper.Map<IList<OrderItemModel>>(o.Items) )); In order to do this, I need a reference to IMappingEngine. When the mapping engine is being configured, I

How to generate a dependency diagram from a set of XSD files?

阅读更多关于 How to generate a dependency diagram from a set of XSD files?

See the title: I have around 50 XSD files importing each other (with tags) and I need to analyze their dependencies. Do you know any software (preferably free) to generate a dependency diagram automatically from these files? I did not find any existing program to do that, so... I developed my own! It is called GraphVisu . There is a first program to generate the graph structure from seed XSD files, and another one to visualise graphs. I also included a detection of clusters of interrelated nodes (called " strongly connected components " in graph theory). Feel free to use it! I am not aware of