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$ curl repovive.com/roadmaps/javascript/variables-data-types/why-matters

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$ curl repovive.com/roadmaps/javascript/variables-data-types/why-matters

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Why === Matters - Variables & Data Types | JavaScript | Repovive

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JavaScript22 sections · 783 units18h total

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Why === Matters

Real-world bugs

Loose equality causes real bugs:

let input = "0"  // User typed "0"

if (input == false) {
  // This runs! "0" == false is true
  console.log("No input provided")
}

With ===, this bug is obvious:

if (input === false) {
  // This doesn't run
  // "0" is a string, false is a boolean
}

Teams often enforce === with linter rules. It's one of the easiest ways to prevent bugs.