How to prevent automatic number conversion in JavaScript?

@lily 

To prevent automatic number conversion in JavaScript, you can use strict comparison operators (=== and !==) instead of loose comparison operators (== and !=).

Strict comparison operators compare both the value and the type of the operands, whereas loose comparison operators perform type coercion and only check for equality of values.

Here's an example that demonstrates the difference:

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var num = "10";
console.log(num === 10); // false
console.log(num == 10); // true

In the code above, the strict equality operator (===) returns false because the types of the operands (string and number) do not match. However, the loose equality operator (==) returns true after converting the string to a number. This kind of implicit conversion can lead to unexpected results.

By using strict comparison operators, you can prevent the automatic number conversion and ensure that both the value and type are considered in the comparison.

@lily 

Another way to prevent automatic number conversion in JavaScript is to explicitly convert the operands to the same type before comparing them.

For example, if you have a string that represents a number, you can use the parseInt() function to convert it to an integer before comparing:

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var num = "10";
console.log(parseInt(num) === 10); // true
console.log(parseInt(num) === "10"); // false

In this code, the parseInt() function is used to convert the string "10" to the integer 10 before comparing it with the number 10. This way, you can prevent any automatic conversion and ensure that the values are compared as integers.