Why does (0 < 5 < 3) evaluate to true in JavaScript?

JavaScript's Comparative Conundrum: Deciphering the Truth Within (0 < 5 < 3)

In the realm of JavaScript, a peculiar observation emerges: why does the expression (0 < 5 < 3) evaluate to true? This enigmatic behavior stems from the language's evaluation rules, known as order of operations.

To unravel this mystery, we must delve into the sequence of operations performed by the expression:

1. Parentheses First: Since there are no parentheses, this step is skipped.
2. Exponentiation: There is no exponentiation, so we move on.
3. Multiplication and Division: Again, these operators are absent.
4. Addition and Subtraction: We have neither addition nor subtraction.

5. Comparison: Here's where the magic happens. The expression is evaluated as ((0 < 5) < 3).

   • First, 0 is compared to 5, resulting in true.
   • The result of this comparison (true) is then compared to 3. However, JavaScript treats true as 1 and false as 0. So, 1 is compared to 3, producing true.

Hence, the entire expression (0 < 5 < 3) reduces to ((true) < 3), which is ultimately true. This explains why it returns true, even though 0 is neither less than 5 nor 3.

Similarly, (0 < 5 < 2) also evaluates to true for the same reason. However, (0 < 5 < 1) returns false because (true) is compared to 1, yielding false.

While this quirk may seem fascinating, its practical applications are limited. However, it serves as a testament to the importance of understanding order of operations in JavaScript programming.

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