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Linting Review

"Linting" can be such a vague and confusing term. I want to go over a few of the most common and useful checks that ESLint warns about, just so you can see a few more examples.

Unused Variables (No-Unused-Vars)

This is one of the most common checks. It warns you about variables, functions, or parameters that are declared but never used.

let unusedVariable; // Warning: 'unusedVariable' is defined but never used

Misleading Comparisons (eqeqeq)

This rule enforces using === and !== instead of == and != to avoid type coercion issues.

// Warning: Expected '===' and instead saw '=='
if (value == "10") {
  // ...
}

Invalid Console Calls (No-Console)

This rule disallows the use of the console object.

console.log("Something went terribly wrong! Contact Boots immediately."); // Warning: Unexpected console statement.

Prefer Template Literals (Prefer-Template)

Before:

const message = "Hello, " + name + "!"; // Warning: Use template literals instead of string concatenation

After:

const message = `Hello, ${name}!`;