/**
 * convenience function to supply a default value if the given value is not specified
 */
export declare function _default<T>(value: T, defaultValue: T): T;
export declare function isAssignableFrom(entryType: any, assignableTo: any): boolean;
/**
 * a function called on an object instance that will return the desired property value
 */
export interface ReadMethod<Type> {
    (): Type;
}
/**
 * a function called on an object instance that will set the desired property value
 */
export interface WriteMethod<Type> {
    (value: Type): void;
}
/**
 * parameters used to create a PropertyDescriptor
 */
export interface PropertyDescriptorParams<T> {
    type: any;
    read: ReadMethod<T>;
    write: WriteMethod<T>;
}
/**
 * an interface to read and write a value into an object
 */
export declare abstract class PropertyDescriptor {
    private propertyType;
    private readMethod;
    private writeMethod;
    constructor(params: PropertyDescriptorParams<any>);
    getPropertyType(): any;
    getReadMethod(): ReadMethod<any>;
    getWriteMethod(): WriteMethod<any>;
}