Can JavaScript omit semicolons?

JavaScript is a very popular programming language that is widely used in various web pages, mobile applications, and server-side code. Unlike other programming languages, JavaScript allows the semicolon to be omitted at the end of a statement. However, whether this is a good practice has been controversial.

First of all, the JavaScript engine can automatically add a semicolon at the end of the statement. This is because the JavaScript engine automatically adds a semicolon at the end of each statement according to syntax rules when interpreting the code. This means that even if you omit semicolons in your code, the JavaScript engine will still add them when necessary.

Secondly, omitting the semicolon may cause errors. When you omit semicolons in your code, the JavaScript engine may not interpret your code correctly, resulting in an error. For example, when you omit a semicolon at the end of a statement, if the next line of code is a block of code that begins with an opening bracket, square bracket, or backtick (`), the JavaScript engine may treat the two lines of code as one statement, resulting in a syntax error.

Additionally, omitting semicolons can cause problems when using JavaScript frameworks or writing large code bases. This is because in this case, multiple developers may be writing the code, each with a different coding style. If one developer likes to omit semicolons and another doesn't, it can cause unpredictable problems and bugs.

Finally, omitting semicolons can make code difficult to maintain. Although some programmers believe that omitting semicolons makes code cleaner, in reality, it can make code difficult to read and understand. During long-term maintenance, certain lines of code may need to be added or removed, and omitting semicolons can cause confusion and make maintenance more difficult.

To sum up, the JavaScript engine can automatically add a semicolon at the end of a statement, but when writing code, it is best not to omit the semicolon. While omitting semicolons can make your code more compact, it can lead to bugs and maintenance issues. So, when writing JavaScript code, follow best coding practices and add a semicolon at the end of every statement. This ensures your code is easy to understand and maintain, and improves code quality.

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