void expression void(expression)
The void operator has an operator precedence ie., the priority will be given to operators while parsing a statement that has more than one operator performing operations in it. Here, we have used the parenthesis, to express the purpose of the expression, according to its precedence.
For instance, consider the below example:
void (10 == '10') // undefined void 10 == '10' // false
For the 1st case, when the number is compared with string, inside the parenthesis with the void keyword, it returns undefined whereas in the 2nd case, when the expression is evaluates directly with the void keyword, it returns false.
Example: This example describes the returning undefined value.
void 0 can be used as a placeholder URL that represents an onclick event is tied to the link to perform the actual action. The void 0 is also commonly used in code downsizing, as it is a way of writing undefined.
There are 3 instances where the void operator can be used:
Example: In this example, the link changes the color of the background to green without returning any value to the browser.
Output: The link will be recognized by the browser but the link doesn’t react at all. When 0 is passed to void as an argument, it does nothing or returns nothing. Here “Click here and do nothing” link doesn’t do anything at all, as depicted in the output.
Suppression of Arrow Functions: Arrow functions provide a braceless syntax to return the value of an expression. To ensure that the return value of the function expression (when it is of no use) doesn’t affect the code in any way, it can be passed into a void operator.
Example: This example explains the returning the value of an expression.
Returning Undefined Value on Purpose: We can convert any variable’s value to an undefined type.