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# Decorator Helpers
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Support for decorator syntax including method decorators, class decorators, and property decorators.
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## Capabilities
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### Core Decorator Functions
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#### _decorate
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Applies decorators to class members and classes.
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```javascript { .api }
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/**
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 * Applies decorators to class members and classes
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 * @param {Array} decorators - Array of decorator functions
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 * @param {Function|Object} target - Target class or prototype
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 * @param {string|symbol} key - Property key (for member decorators)
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 * @param {Object} desc - Property descriptor
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 * @returns {any} Decorated result
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 */
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function _decorate(decorators, target, key, desc): any;
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```
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**Usage Example:**
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```javascript
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// For: @decorator class MyClass {}
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_decorate([decorator], MyClass);
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// For: @decorator method() {}
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_decorate([decorator], MyClass.prototype, "method", descriptor);
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```
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#### _apply_decorated_descriptor
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Applies decorated descriptors to object properties.
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```javascript { .api }
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/**
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 * Applies decorated descriptors to object properties
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 * @param {Object} target - Target object
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 * @param {string|symbol} property - Property key
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 * @param {Array} decorators - Array of decorators
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 * @param {Object} descriptor - Original property descriptor
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 * @param {Object} context - Decorator context
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 * @returns {Object} Updated descriptor
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 */
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function _apply_decorated_descriptor(target, property, decorators, descriptor, context): Object;
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```
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### Stage 3 Decorator Support
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#### _apply_decs_2203_r
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Applies Stage 3 decorators following the 2022-03 revision.
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```javascript { .api }
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/**
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 * Applies Stage 3 decorators following the 2022-03 revision
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 * @param {Function} targetClass - Target class
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 * @param {Array} memberDecs - Member decorators
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 * @param {Array} classDecs - Class decorators
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 * @param {Array} classDecsHaveThis - Class decorators with this context
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 * @param {number} instanceBrand - Instance brand value
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 * @returns {Object} Decorated class information
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 */
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function _apply_decs_2203_r(targetClass, memberDecs, classDecs, classDecsHaveThis, instanceBrand): Object;
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```
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### Initializer Helpers
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#### _initializer_define_property
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Defines properties using initializer functions.
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```javascript { .api }
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/**
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 * Defines properties using initializer functions
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 * @param {Object} target - Target object
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 * @param {string|symbol} key - Property key
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 * @param {Object} descriptor - Property descriptor
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 * @param {Object} context - Definition context
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 * @param {Function} initializer - Initializer function
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 */
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function _initializer_define_property(target, key, descriptor, context, initializer): void;
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```
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#### _initializer_warning_helper
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Provides warnings for initializer usage.
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```javascript { .api }
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/**
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 * Provides warnings for initializer usage
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 * @param {Object} descriptor - Property descriptor
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 * @param {Object} context - Usage context
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 * @returns {Function} Warning function
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 */
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function _initializer_warning_helper(descriptor, context): Function;
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```
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### Descriptor Utilities
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#### _class_apply_descriptor_get
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Applies getter descriptors to class members.
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```javascript { .api }
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/**
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 * Applies getter descriptors to class members
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 * @param {Object} target - Target object
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 * @param {Object} descriptor - Getter descriptor
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 * @returns {any} Getter result
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 */
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function _class_apply_descriptor_get(target, descriptor): any;
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```
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#### _class_apply_descriptor_set
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Applies setter descriptors to class members.
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```javascript { .api }
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/**
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 * Applies setter descriptors to class members
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 * @param {Object} target - Target object
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 * @param {Object} descriptor - Setter descriptor
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 * @param {any} value - Value to set
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 * @returns {any} Set value
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 */
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function _class_apply_descriptor_set(target, descriptor, value): any;
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```
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#### _class_apply_descriptor_update
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Applies update descriptors to class members.
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```javascript { .api }
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/**
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 * Applies update descriptors to class members
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 * @param {Object} target - Target object
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 * @param {Object} descriptor - Update descriptor
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 * @param {Function} updateFn - Update function
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 * @returns {any} Updated value
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 */
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function _class_apply_descriptor_update(target, descriptor, updateFn): any;
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```
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#### _class_apply_descriptor_destructure
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Applies destructure descriptors to class members.
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```javascript { .api }
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/**
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 * Applies destructure descriptors to class members
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 * @param {Object} target - Target object
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 * @param {Object} descriptor - Destructure descriptor
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 * @returns {any} Destructured value
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 */
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function _class_apply_descriptor_destructure(target, descriptor): any;
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```
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#### _class_extract_field_descriptor
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Extracts field descriptors from class members.
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```javascript { .api }
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/**
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 * Extracts field descriptors from class members
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 * @param {Object} target - Target object
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 * @param {string|symbol} key - Property key
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 * @param {boolean} isStatic - Whether field is static
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 * @returns {Object} Field descriptor
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 */
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function _class_extract_field_descriptor(target, key, isStatic): Object;
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```
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### TypeScript Decorator Support
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#### _ts_decorate
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TypeScript-specific decorator implementation (re-exported from tslib).
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```javascript { .api }
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/**
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 * TypeScript-specific decorator implementation (re-exported from tslib.__decorate)
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 * @param {Array} decorators - Array of decorators
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 * @param {Function|Object} target - Target class or prototype
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 * @param {string|symbol} key - Property key
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 * @param {Object} descriptor - Property descriptor
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 * @returns {any} Decorated result
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 */
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function _ts_decorate(decorators, target, key, descriptor): any;
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```
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#### _ts_metadata
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Handles TypeScript metadata for decorators (re-exported from tslib).
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```javascript { .api }
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/**
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 * Handles TypeScript metadata for decorators (re-exported from tslib.__metadata)
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 * @param {string} metadataKey - Metadata key
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 * @param {any} metadataValue - Metadata value
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 * @returns {Function} Metadata decorator
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 */
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function _ts_metadata(metadataKey, metadataValue): Function;
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```
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#### _ts_param
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TypeScript parameter decorator helper (re-exported from tslib).
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```javascript { .api }
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/**
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 * TypeScript parameter decorator helper (re-exported from tslib.__param)
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 * @param {number} paramIndex - Parameter index
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 * @param {Function} decorator - Parameter decorator
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 * @returns {Function} Parameter decorator function
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 */
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function _ts_param(paramIndex, decorator): Function;
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```