JavaScript is one of the most popular programming languages today and is widely used in website, mobile application and software development. In the process of learning and using JavaScript, you may often see the term "the line behind JavaScript", so what does it mean?
First of all, it is necessary to clarify what the "line after JavaScript" refers to. Here, it often refers to "semicolon (;)", which means that in JavaScript, the semicolon can play the role of "the line behind JavaScript".
JavaScript is an interpreted language, and its execution flow is to interpret and execute the code line by line. During this process, the compiler needs to identify the end point of each line of code. In some languages, this end point is represented by a "newline character". But in JavaScript, the end of a statement is usually not represented by a newline character, but by a semicolon ";".
Therefore, when you write JavaScript code, add a semicolon at the end of each statement, which can make the code more standardized, readable and maintainable. But in JavaScript, if you omit the semicolon, sometimes no error will be reported, and the semicolon will even be automatically completed in some cases. This is because the compiler will automatically infer the position of the missing semicolon based on the structure and syntax of the code, but this behavior is unstable and is not conducive to the correctness and readability of the code.
In actual use, it is recommended to always add a semicolon at the end of each statement, which can not only avoid unnecessary errors, but also make the code easier to read and maintain. In addition, standardized coding style can also make your code more consistent with other people's code and improve the readability of the code.
In addition to the semicolon, JavaScript has other symbols that can be used to indicate the end of code, such as the right bracket "}" of a code block or the end check "return" of a function. But in actual development, most JavaScript code ends with a semicolon. Therefore, it is very important to use the "line after JavaScript" correctly, that is, the semicolon.
In short, the line after JavaScript refers to the "semicolon", and the semicolon is usually used to indicate the end of a statement in JavaScript. In actual development, always using semicolons can make your code more standardized, readable, and maintainable.
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