Is Declaring Global Variables Inside Functions Without \"var\" a RAM Optimization Strategy?

The Horror of Implicit Globals: Declaring Variables Without the 'var' Keyword

W3Schools states that declaring a variable without using "var" makes it a global variable. This raises the question of whether declaring global variables within a function is advantageous. Can it optimize RAM usage or improve code efficiency?

The Reality: No RAM Benefits

Contrary to beliefs, there is no RAM or performance advantage in declaring global variables inside functions without the "var" keyword. Instead, this practice can lead to undesirable consequences.

Implicit Global Variables: A Typographical Nightmare

Consider the following example:

function foo() {
    variable1 = 5;
    variable2 = 6;
    return variable1 + variable2;
}

Due to a typo in the declaration of "variable2," this code produces NaN instead of the expected 11. Worse, it inadvertently creates a global variable with the misspelled name "varaible2."

Console Output:

console.log(foo());     // NaN
console.log(varaible2); // 6?!?!?!

This unintended behavior can introduce errors, making it challenging to debug your code. Hence, it is recommended to consistently use the "var" keyword to avoid the "Horror of Implicit Globals" and ensure the predictability of your code.

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