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Rslint

    prefer-const

    Configuration

    PresetConfigured Value
    ✅ ts.configs.recommended"error"
    rslint.config.ts
    import { defineConfig, js } from '@rslint/core';

export default defineConfig([
  js.configs.recommended,
  {
    rules: {
      'prefer-const': 'error',
    },
  },
]);

    Rule Details

    Requires const declarations for variables that are never reassigned after declared. If a variable is never reassigned, using the const declaration is better because it makes the intent clear that the value is not intended to be changed.

    Examples of incorrect code for this rule:

    let x = 1;
let obj = { key: 0 };
for (let x in obj) {
  console.log(x);
}
for (let x of [1, 2, 3]) {
  console.log(x);
}

    Examples of correct code for this rule:

    const x = 1;
const obj = { key: 0 };
let y = 1;
y = 2;
let z;
z = 1;
for (const x in obj) {
  console.log(x);
}
for (const x of [1, 2, 3]) {
  console.log(x);
}

    Original Documentation