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Mind map closure Before understanding closures, let's learn about the memory release of the parent scope and stack. Concept of parent scope Where is the parent scope of a function created and who is the parent scope var a = 10 function foo(){ console.log(a) } function sum() { var a = 20 foo() } sum() /* output 10 / ...

webpack and browser caching We use webpack to package our modular application. Webpack will generate a deployable / dist directory, and then place the packaged content in this directory. As long as the contents in the / dist directory are deployed on the server, the client (usually the browser) can access the server's website and its resources ...

Based on the Office core technology independently developed by Yongzhong Software Co., Ltd. for more than ten years, Yongzhong cloud service platform provides a variety of Saas services for document processing and processing, and realizes a variety of functions such as document online preview, document online editing, document format conversion ...

I think everyone must have read the explanations and sermons of various "strategic models" more or less. This article is to "clarify" the strategic models and try to answer the following questions: 1. How does the policy pattern optimize the business logic code structure? 2. How can you kill a chicken with an ox knife? Jus ...

First, take a look at a classic code and count its execution time: // test_predict.cc #include <algorithm> #include <ctime> #include <iostream> int main() { const unsigned ARRAY_SIZE = 50000; int data[ARRAY_SIZE]; const unsigned DATA_STRIDE = 256; for (unsigned c = 0; c < ARRAY_SIZE; ++c) data[c] = std::r ...

preface The function of button permission control is actually described in the previous article Page permission management It also contains this function, but it is not highlighted, so now write a separate article to record it 1, What is button permission control? Just finished A background management system, which is useful for button per ...

javascript article 1, Data type There are several types of JavaScript Basic data types: undefined, null, boolean, number, string, symbol (new data type of ES6)Reference data types: object, array, function (collectively referred to as object) Data type detection typeof ， for basic data types, the correct type can be displayed except ， nul ...

What is EventBus? event bus refers to the bus Using a fixed bus stop to handle boarding and alighting events is compared to subscription and event distribution In programming, eventbus is usually used to transmit data in the form of publish and subscribe Subscribe to events in advance. When events are triggered, you can r ...

preface Today, I encountered a data processing problem. Although it was solved, the process seems very cumbersome, the code is not elegant, and the logic is very cumbersome. With reduce, it can be easily solved and beautiful. Let's learn about reduce first, and then give an example of how to use reduce and its difference from map I Use o ...

Stopwatch is interpreted as a timer, also known as stopwatch and stop watch. Obviously, it records time. How to use Stopwatch stopwatch = Stopwatch.createStarted(); doSomething(); stopwatch.stop(); // optional long millis = stopwatch.elapsed(MILLISECONDS); // formatted string like "12.3 ms"} log.info("time: " + stopwatch); Android ...