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StringString.prototype.localeComparebeginner

String.prototype.localeCompare() — equal strings return 0

📖 Usage Example
'apple'.localeCompare('banana')   // → negative
'banana'.localeCompare('apple')   // → positive
'abc'.localeCompare('abc')        // → 0

Use localeCompare() to compare strings in a locale-aware way, returning negative, zero, or positive.

String.prototype.localeCompare()

str.localeCompare(compareString) returns:

  • 0 if the strings are equal
  • a negative number if str comes before compareString
  • a positive number if str comes after compareString

Challenge: Implement areEqual(a, b) that returns true when a.localeCompare(b) === 0.

areEqual('abc', 'abc') // → true
areEqual('abc', 'def') // → false
💡 Hints (1)
  • • `.localeCompare()` returns `0` for equal strings.