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# Configuration Transformation
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Core functionality for converting object-based ESLint rules to flat config format, providing a more intuitive way to write ESLint configurations.
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## Capabilities
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### matchToFlat Function
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Converts object-based rule configurations to ESLint flat config arrays. This allows writing ESLint configs using objects instead of verbose arrays.
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```javascript { .api }
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/**
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 * Converts object-based rule configurations to flat config arrays
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 * @param {Object} config - Object with file patterns as keys and rules as values
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 * @returns {Array<Object>} Array of ESLint flat config objects
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 */
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function matchToFlat(config);
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```
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**Parameters:**
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- `config` (Object): Configuration object where keys are file patterns and values are rule objects
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**Returns:**
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Array of objects with `files` and `rules` properties matching ESLint flat config format.
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**Usage Examples:**
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```javascript
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const { matchToFlat } = require('@putout/eslint-flat');
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// Basic transformation
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const match = {
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  'bin/putout.mjs': {
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    'n/hashbang': 'off',
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  },
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  '**/register.mjs': {
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    'n/no-unsupported-features/node-builtins': 'off',
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  },
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};
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const result = matchToFlat(match);
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console.log(result);
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// Output:
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// [
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//   {
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//     files: ['bin/putout.mjs'],
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//     rules: { 'n/hashbang': 'off' }
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//   },
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//   {
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//     files: ['**/register.mjs'],
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//     rules: { 'n/no-unsupported-features/node-builtins': 'off' }
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//   }
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// ]
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// Multiple rules per pattern
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const complexMatch = {
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  '*.test.js': {
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    'jest/expect-expect': 'off',
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    'jest/no-disabled-tests': 'warn',
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    'complexity': ['error', 15],
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  },
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};
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const complexResult = matchToFlat(complexMatch);
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// Result: [{ files: ['*.test.js'], rules: { 'jest/expect-expect': 'off', ... } }]
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```
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**Use in ESLint Configuration:**
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```javascript
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const { matchToFlat } = require('@putout/eslint-flat');
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const { safeAlign } = require('eslint-plugin-putout/config');
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const match = {
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  'src/**/*.js': {
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    'no-console': 'warn',
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  },
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  'test/**/*.js': {
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    'no-console': 'off',
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  },
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};
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module.exports = [
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  ...safeAlign,
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  ...matchToFlat(match),
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];
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// Export the match object for reuse
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module.exports.match = match;
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```
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This approach provides several benefits:
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- More readable configuration structure
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- Easier to maintain and modify rules
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- Better organization of file-specific rules
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- Ability to export the match object for reuse in monorepos