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non-nullable-type-assertion-style

Enforce non-null assertions over explicit type casts.

This rule detects when an as cast is doing the same job as a ! would, and suggests fixing the code to be an !.

Attributes

  • Included in configs
    • ✅ Recommended
    • 🔒 Strict
  • Fixable
    • 🔧 Automated Fixer
    • 💡 Suggestion Fixer
  • 💭 Requires type information

Rule Details​

Examples of code for this rule:

const maybe = Math.random() > 0.5 ? '' : undefined;

const definitely = maybe as string;
const alsoDefinitely = <string>maybe;

Options​

.eslintrc.cjs
module.exports = {
  "rules": {
    "@typescript-eslint/non-nullable-type-assertion-style": "warn"
  }
};

This rule is not configurable.

When Not To Use It​

If you don't mind having unnecessarily verbose type casts, you can avoid this rule.

Resources​