JavaScript TypeError - Variable "x" redeclares argument
Last Updated :
22 May, 2023
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This JavaScript exception variable redeclares argument occurs in strict-mode only and if the variable name which is also function parameter has been redeclared with the var keyword.
Message:
TypeError: variable "x" redeclares argument (Firefox)
Error Type:
TypeError
Cause of the Error: A variable which is the parameter of the function has been re-declared with the var keyword inside the function.
Example 1: In this example, the variable('varName') has been redeclared.
'use strict';
function fun(varName) {
let varName = 'This is GFG'; // Error Here
}
Output:
TypeError: variable "varName" redeclares argument
Example 2: In this example, the variable('argName') has been redeclared and function is called as well.
'use strict';
function fun2(argName) {
let argName = 'This is gfg'; // Error Here
}
fun2('This is GeeksFooGeeks');
Output:
TypeError: variable "argName" redeclares argument
