cyclic-reference

问题 Trying to find a good and proper pattern to handle a circular module dependency in Python. Usually, the solution is to remove it (through refactoring); however, in this particular case we would really like to have the functionality that requires the circular import. EDIT : According to answers below, the usual angle of attack for this kind of issue would be a refactor. However, for the sake of this question, assume that is not an option (for whatever reason). The problem: The logging module

问题 Trying to find a good and proper pattern to handle a circular module dependency in Python. Usually, the solution is to remove it (through refactoring); however, in this particular case we would really like to have the functionality that requires the circular import. EDIT : According to answers below, the usual angle of attack for this kind of issue would be a refactor. However, for the sake of this question, assume that is not an option (for whatever reason). The problem: The logging module

问题 Today I started using MapStruct to create my Model to DTO converters for my project and i was wondering if it handled cyclic references automatically but it turned out it doesn't. This is the converter i made to test it: package it.cdc.snp.services.rest.giudizio; import org.mapstruct.Mapper; import org.mapstruct.Mapping; import org.mapstruct.Mappings; import org.mapstruct.factory.Mappers; import org.springframework.stereotype.Component; import it.cdc.snp.dto.entita.Avvisinotifica; import it

问题 Today I started using MapStruct to create my Model to DTO converters for my project and i was wondering if it handled cyclic references automatically but it turned out it doesn't. This is the converter i made to test it: package it.cdc.snp.services.rest.giudizio; import org.mapstruct.Mapper; import org.mapstruct.Mapping; import org.mapstruct.Mappings; import org.mapstruct.factory.Mappers; import org.springframework.stereotype.Component; import it.cdc.snp.dto.entita.Avvisinotifica; import it

问题 I have a class that has __eq__ and __hash__ overridden, to make its objects act as dictionary keys. Each object also carries a dictionary, keyed by other objects of the same class. I get a weird AttributeError when I try to deepcopy the whole structure. I am using Python 3.6.0 on OsX. From Python docs it looks as if deepcopy uses a memo dictionary to cache the objects it has already copied, so nested structures should not be a problem. What am I doing wrong then? Should I code up my own _

问题 I see many Q/A on how to detect a loop in linked list, but I want to understand is why we want to do that, in other words what are the practical use cases of detecting a loop in a linked list 回答1: In real life, you'll probably never need to detect a loop in a linked list, BUT the algorithms for doing that are important and I have used them in real life many times. Pretty often, for example, I will process a linked data structure recursively when it's supposed to be tree-shaped. If it isn't

问题 I see many Q/A on how to detect a loop in linked list, but I want to understand is why we want to do that, in other words what are the practical use cases of detecting a loop in a linked list 回答1: In real life, you'll probably never need to detect a loop in a linked list, BUT the algorithms for doing that are important and I have used them in real life many times. Pretty often, for example, I will process a linked data structure recursively when it's supposed to be tree-shaped. If it isn't

问题 Sorry for my inexperience with C++, but I spent quiet some time with solving a cyclic dependency issue and hence posing this. I am trying to represent a Adjacency List in C++. I have struct Node , struct Node{ int data; unordered_set<Node, Hash> links; bool operator == (Node const& other) const{ return (data == other.data); } Node(){ } Node(int data){ this->data = data; } }; and I have my Hash functor struct Hash { size_t operator()(const Node &node) const { return node.data; }; }; I noticed

问题 I have project in PlayFramework. It has one main project without any code/logic. And it have few submodules: main: admin common shop Modules: admin and shop will base on common module (classes like: user, role, permission), so I have to configure it that way: lazy val shop = project.in(file("modules/shop")) .dependsOn(cirs) .dependsOn(common) .dependsOn(admin) lazy val admin = project.in(file("modules/admin")) .dependsOn(cirs) .dependsOn(common) .dependsOn(shop) But in module common I have

问题 I am trying to implement a cyclic linked data structure in Rust. My Node s are defined as: #[derive(Debug)] enum Node<'a> { Link(&'a Node<'a>), Leaf, } I am trying to build a minimal structure like this (extra brackets for better lifetime visibility): fn main() { let placeholder = Node::Leaf; { let link1 = Node::Link(&placeholder); { let link2 = Node::Link(&link1); println!("{:?}", link2); } // link2 gets dropped } // link1 gets dropped } This works, but now I don't know how to replace the