init | 易学教程

What is the meaning of 'self' and 'init' expressions in Python? [closed]

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I don't understand what these are used for, particularly the self argument? Could some please explain this to me and why on earth you would want to pass this in? Also, I've always thought __init__ was for 'initialisation', but it didn't occur to me that I've never had to put anything in here before. Could someone give me an easy example? edit: i just get so confused everytime i see self being passed into a function, or something of the like. self is the object you're calling the method on. It's a bit like this in Java. __init__ is called on each object when it is created to initialise it. It's

Creating a task that runs before all other tasks in gradle

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问题 I need to create an initialize task that will run before all other task when I execute it. task A { println "Task A" } task initializer { println "initialized" } If I execute gradle -q A , the output will be: >initialized >Task A Now if i'll add: task B { println "Task B" } Execute gradle -q B , and I get: >initialized >Task B So it doesn't matter which task I execute, it always get "initialized" first. 回答1: You can make every Task who's name is NOT 'initializer' depend on the 'initializer'

Initializing jquery from Node

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I am creating a new project using the following: $mkdir X $cd X $npm install jquery Then create a new app.js file: var http = require('http'); var $ = require('jquery'); console.log("http="+ http); console.log("$="+ $); console.log("$.getJSON="+ $.getJSON); Output is: http=[object Object] $=function ( w ) {...} $.getJSON=undefined Why is $.getJSON undefined ? Using latest io.js v2.4.0. Yan Foto You are trying to create an XHR from within Node.js. This is not going to work since Node.js is simply a JavaScript runtime and is not the same as a browser. If you want to fetch something from

Emacs init.el file doesn't load

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问题 When I open emacs, the following messages appear in the *Messages* buffer, and my init.el file (located at ~/.emacs.d/init.el ) doesn't load. Loading 00debian-vars...done Loading /etc/emacs/site-start.d/50cedet-common.el (source)... Error while loading 50cedet-common: Cannot open load file: cedet-autogen Loading /etc/emacs/site-start.d/50dictionaries-common.el (source)... Loading debian-ispell... Loading /var/cache/dictionaries-common/emacsen-ispell-default.el (source)...done Loading debian

calling init for multiple parent classes with super? [duplicate]

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问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: Can Super deal with multiple inheritance? Python inheritance? I have a class structure (below), and want the child class to call the __init__ of both parents. Is this possible to do in a 'super' way or is it just a terrible idea? class Parent1(object): def __init__(self): self.var1 = 1 class Parent2(object): def _init__(self): self.var2 = 2 class Child(Parent1, Parent2): def __init__(self): ## call __init__ of

Zend Framework Bootstrap Issue

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I have been working on a new installation of a Zend Framework application for a while now, and I cannot figure out what's going on. I have two custom action helpers I would like to use and I would like to initialize those in the bootstrap. But it seems as though my _init functions are not being called at all. In the index.php that starts the application I have: require('Zend/Application.php'); $app = new Zend_Application(APPLICATION_ENV, APPLICATION_PATH .'/configs/application.ini'); $app->bootstrap()->run(); Here's what I have in the application.ini file: [production] appnamespace =

Implementation of -init vs. +initialize

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问题 Can anyone explain why we need to include if (self == SomeClass class) inside the +initialize method? I’ve found similar questions (listed below), but didn’t find any specific clarifications: Objective-C: init vs initialize Should +initialize/+load always start with an: if (self == [MyClass class]) guard? Everyone says that if you don’t implement/override +initialize in Subclass, then it’s going to call the parent class twice. Can anyone explain that part in particular, specifically why does

ubuntu10.04的初始化

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对于虚拟化，我们希望共享虚拟光盘上的系统，每个虚拟机的个性配置和数据在各自的虚拟硬盘上！这样我们只需维护一个共享的系统和各自的数据，这样虽然系统只读，不会感染病毒，但光盘不能更新，容易被攻击！进而我们想到用共享的只读虚拟硬盘存放系统。而linux的系统结构要求etc、bin、sbin、lib必须在同一个分区（ / ），usr、var、home、boot等系统目录及自定义目录可以放在其他分区。这就要求我们必须从etc目录中分离出跟本机有关的文件或目录，或只保留能引导到挂载其他分区的一小部分，要动 etc ，必须精研初始化！ ubuntu的初始化一直在变，确实启动越来越快，但文档没能跟得上！辩证地看，对于字符界面的服务器来说，BSD风格的init脚本，更利于管理员跟踪！网上很多资料，太老了，基本没有参考价值！10.04的初始化用的是基于事件的upstart。开始动手： 1、/etc复制到另一个分区/TaoHong/etc 2、精简/etc，经过两天实验，缺一个文件都启动不了，/etc只保留： #ls -p /etc default/ fstab group gshadow init/ mtab passwd shadow 3、修改fstab /dev/sda1 / ext4 ro 0 1 # /根只读 /dev/sdb1 /TaoHong

What's the differences between member initializer list and default member initializer on non-static data member?

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问题 I'd like to understand what's the differences of using one form rather than the other (if any). Code 1 (init directly on variables): #include <iostream> using namespace std; class Test { public: Test() { cout<< count; } ~Test(); private: int count=10; }; int main() { Test* test = new Test(); } Code 2 (init with initialization list on constructor): #include <iostream> using namespace std; class Test { public: Test() : count(10) { cout<< count; } ~Test(); private: int count; }; int main() {

swift - Initialize view controller from storyboard by overriding init

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问题 I have a ViewController instance defined in a storyboard. I can initialize it by the following var myViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewControllerWithIdentifier("myViewControllerIdentifier") as! ViewController Is there a way to override the init method of ViewController so that I can initialize it using var myViewController = ViewController() I tried overriding init convenience init() { self = UIStoryboard(name: "Main", bundle: nil)