scope

问题 I'm trying to receive some data being sent to a webhook and work with it. I'm able to receive the data and convert it to a json String however I want to assign the json String to a global variable so I can use it elsewhere, and in other functions. I'm declaring the variable first and then trying to assign the json string to it when i receive it but it doesn't seem to be working - the variable is still 'undefined' var jsonData; function doPost(e){ try{ var jsonString = e.postData

问题 I'm trying to receive some data being sent to a webhook and work with it. I'm able to receive the data and convert it to a json String however I want to assign the json String to a global variable so I can use it elsewhere, and in other functions. I'm declaring the variable first and then trying to assign the json string to it when i receive it but it doesn't seem to be working - the variable is still 'undefined' var jsonData; function doPost(e){ try{ var jsonString = e.postData

问题 We are having @Configuration class, but it doesn't contain any bean definition and as it is a legacy class written by someone i don't want to remove the @Configuration annotation even while there is no bean definition. Somehow i want to perform logic on shutdown hook of web application but somehow i am not able to get bean from context in the contextDestroyed() method so i want to use @PreDestroy on that @Configuration class. Does any one specify what is the default scope of the

问题 I'm trying to mass encode video files in x265 and wanted to come up with a batch file that could automate the process. In order to expedite things, I found that having 3 instances of ffmpeg called with 2 threads resulted in ideal encoding times, however I've tried all day yesterday to come up with a way to get a batch file that will call 3 instances and then call new ones when they complete. So far, this is where I am: PARENT BATCH @echo off Setlocal EnableDelayedExpansion SET /A COUNT=0 for

问题 I am trying to add a condition_variable to handle threads, but get a compilation error at this line: this->cv.wait(lk, []{return this->ready;}); Looks like the for the variable this->ready, the 'this' is not in the right scope. In Java this can be handled with TestThread.this, is there anything in C++ doing the same? void TestThread::Thread_Activity() { std::cout << "Thread started \n"; // Wait until ThreadA() sends data { std::unique_lock<std::mutex> lk(m); this->cv.wait(lk, []{return ready;

问题 Please note this is not duplicate of existing var vs let scope. I'm aware of the scope of var and let declarations and differences. But below scenario I could not justify with the understanding I had with let and var difference. In the below code, function foo accepts argument by name 'x' which has implicit let scope - as I cannot redeclare same variable name using let inside that function (uncommenting last line in function foo will throw JS error) "use strict"; function foo(x) { console.log

问题 Please note this is not duplicate of existing var vs let scope. I'm aware of the scope of var and let declarations and differences. But below scenario I could not justify with the understanding I had with let and var difference. In the below code, function foo accepts argument by name 'x' which has implicit let scope - as I cannot redeclare same variable name using let inside that function (uncommenting last line in function foo will throw JS error) "use strict"; function foo(x) { console.log

问题 Please note this is not duplicate of existing var vs let scope. I'm aware of the scope of var and let declarations and differences. But below scenario I could not justify with the understanding I had with let and var difference. In the below code, function foo accepts argument by name 'x' which has implicit let scope - as I cannot redeclare same variable name using let inside that function (uncommenting last line in function foo will throw JS error) "use strict"; function foo(x) { console.log

问题 In Ruby, I am aware that I can do things like this: if false var = "Hello" end puts var The application doesn't crash, and var is simply set to nil . I've read that this happens due to the way the Ruby parser works. Why does the same not work for constants? if false MY_CONST = "Hello" end puts MY_CONST => uninitialized constant MY_CONST (NameError) 回答1: TL;DR Local variables are defined when encountered by the parser, while constants are not. However, both must be defined when evaluated by

问题 In bash, if I define a variable inside a script (say, set_var.sh ), I can choose whether those definitions persist after "running" the script. This will depend on how I "run" the script, the options being: sh set_var.sh (variables do not persist) ./set_var.sh (variables do not persist, same as point 1) source set_var.sh (variables persist) This is irrespective from the variable being exported to the environment or not in set_var.sh . Can the same as items 1 and 3 above be achieved with