javascript with or without semicolon

JavaScript with or without semicolon

JavaScript is a widely used scripting language. It is often used for website development and interactive web pages. It is also used for Node.js server-side development and game development. etc. There is a long-standing debate in JavaScript about whether it is better to add a semicolon (;) or not.

Benefits and Disadvantages of Adding Semicolons

In JavaScript, the semicolon is a statement terminator. A statement is a piece of code that performs some action or declares some variable. Without a semicolon, the statement automatically terminates at a newline character. Because the JavaScript executor can add semicolons automatically, it usually works without adding a semicolon. However, there are occasionally special cases where omitting a semicolon can lead to errors and unusual code behavior.

These special cases include:

1. When the beginning of the line is (, [, or `, JavaScript will think that the previous statement has not been completed, and directly combine this line of code with the previous line. The codes are connected together. This will cause errors.

2. After keywords such as return, throw, break, continue, etc., if there is no newline character, JavaScript will automatically fill in a semicolon. If there is a semicolon in the If keywords such as return and throw are added to the end of the previous line of code followed by a value, this value will be regarded as the return value of the statement before the semicolon. In this case, if the statement before the semicolon does not return a value, it will cause unexpected Unexpected behavior.

3. After the and-- operator, if there is no newline character, JavaScript will automatically add a semicolon. This will also cause unexpected behavior.

On the contrary , adding a semicolon ensures code robustness. If you are using multiple libraries and they all require semicolons between code behaviors, then adding semicolons to your code ensures that all code will run correctly. .

Benefits and Disadvantages of Not Using Semicolons

Of course, all coding standards have different standards. Some people even prefer not to use semicolons in JavaScript code. These people think Not using semicolons can make the code more concise, more readable, and reduce the amount of code.

The benefits of not using semicolons include:

1. Performance improvement. JavaScript executor No need to spend time parsing semicolons, and you reap the benefits of minimized code size.

2. Code conciseness. Fewer characters and fewer semicolons generally mean clearer, easier-to-read code. Code.

However, not adding semicolons will also have some opposite disadvantages:

1. Poor maintainability. When using variables in multiple abbreviations and deeply nested statements, The absence of semicolons may make code difficult to understand and maintain.

2. There are issues with compatibility. Some older JavaScript engines may not correctly parse code that does not use semicolons.

In short, the issue of whether to add semicolons or not is decided by coding standards and programming teams. In the JavaScript code you write, you can choose not to use semicolons, but when adding semicolons, you should pay attention to adding them to the appropriate place. to avoid errors and exceptions. If you are entering a teamwork project, be sure to develop consistent coding standards with the rest of the team to ensure code consistency and readability.

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