javascript guard clause

JavaScript
//A good example of using a guard clause is on IF statements
//Example:
//Here is a normal if function:
let x = 0
if (x <= 0) {
 //codes here 
} else {
 //more codes here 
};
//But there are a lot of potential bugs in that code.
//Here is an example of a guard clause:
let x = 0;
if (x <= 0) return //codes / or empty 
if (x > 0) return //codes here

//It lets you write more compact codes, and potentially easier to read
Source

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