Why Does \'one\' > \'four\' Return True in JavaScript?

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Understanding Lexicographic Comparison of Strings in JavaScript

When comparing strings in JavaScript using the greater than operator (>), you may encounter unexpected results. For instance, as exemplified in the given code:

var a = "one";
var b = "four";
a > b; // will return true

Here, we observe that "one" is considered greater than "four". This outcome might seem surprising, but it can be explained by the underlying lexicographic comparison method used by JavaScript.

Lexicographic comparison, often referred to as alphabetical ordering, is a distinctive way of comparing strings that extends beyond the 26-letter English alphabet. It evaluates strings by considering the order of their constituent characters in a defined set of encoding rules.

In JavaScript, strings are primarily compared based on their Unicode code points. Each character within a string is assigned a specific Unicode code point, and lexicographic comparison proceeds by sequentially comparing these codes.

In our example, the character "o" has a Unicode code point of 111, while the character "f" has a Unicode code point of 102. Since "o" comes after "f" in the Unicode sequence, "one" is considered lexicographically greater than "four."

Similarly, if we compare the string "a" to "one" and "four", we find that "a" has a Unicode code point of 97, which is lower than both "o" (111) and "f" (102). Thus, "a" is lexicographically smaller than both "one" and "four."

By understanding the principles behind lexicographic comparison, you can avoid confusion and make informed decisions when working with strings in JavaScript.

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