For AI agents: the complete documentation index is available at https://rslint.rs/llms.txt, the full documentation bundle is available at https://rslint.rs/llms-full.txt, and this page is available as Markdown at https://rslint.rs/rules/unicorn/prefer-array-flat-map.md.
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Rslint

    prefer-array-flat-map

    Added in v0.6.5

    Configuration

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

export default defineConfig([
  unicornPlugin.configs.recommended,
  {
    rules: {
      'unicorn/prefer-array-flat-map': 'error',
    },
  },
]);

    Rule Details

    Prefer Array#flatMap() over chaining Array#map() and Array#flat() when the flat depth is omitted or exactly 1.

    Examples of incorrect code for this rule:

    const foo = bar.map(element => unicorn(element)).flat();
const foo = bar.map(element => unicorn(element)).flat(1);

    Examples of correct code for this rule:

    const foo = bar.flatMap(element => unicorn(element));
const foo = bar.map(element => unicorn(element)).flat(2);
const foo = React.Children.map(children, fn).flat();

    Original Documentation