Why Does '2' > '10' Return True in JavaScript?

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Javascript: Unforeseen String-Integer Comparison Conundrum

In the realm of web development, it is often necessary to compare parameters stored as strings or integers. However, a peculiar bug has surfaced, leaving developers scratching their heads. Integer comparisons seem to behave erratically, as if the parameters are being treated as strings instead.

Consider this baffling example: when the code console.log("2" > "10") is executed, it unexpectedly returns 'true'. This defies all logical expectations, given that 2 is numerically smaller than 10.

So, what's the root of this peculiar behavior? It turns out that Javascript's comparison operators perform lexical comparisons by default. This means that when comparing strings and integers, the strings are treated as Unicode code points and compared character by character. In this case, the leading '2' in the string "2" is lexically greater than the leading '1' in "10", hence the outcome.

To resolve this issue, it is essential to explicitly parse the string parameters into integers. This can be achieved using the parseInt function, as demonstrated in the following code:

console.log(parseInt("2", 10) > parseInt("10", 10));

By parsing the strings into integers, we ensure that numerical comparisons are performed correctly without falling prey to lexical pitfalls.

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