/**
 * Sets form field values from a data object using the name attribute.
 * Supports dot notation for accessing nested properties and array handling.
 *
 * When `context` is provided, `<select>` elements are populated with options
 * before their value is set. The option source is resolved from either the
 * `data-source` attribute or, as a fallback, the select's `name` attribute.
 * The resolved property on `context` can be an array or a method returning
 * an array. The `data-source` attribute may also declare which item
 * properties to use as value and text.
 *
 * @param form - The HTML form element to populate
 * @param data - The data object containing values to set in the form
 * @param context - Optional sources used to populate `<select>` options
 *
 * @example
 * // Basic usage with flat object
 * const form = document.querySelector('form');
 * const data = { name: 'John', email: 'john@example.com' };
 * setFormData(form, data);
 *
 * @example
 * // Using with nested objects via dot notation
 * const form = document.querySelector('form');
 * const data = {
 *   user: {
 *     name: 'John',
 *     contact: {
 *       email: 'john@example.com'
 *     }
 *   }
 * };
 * // Form has fields with names like "user.name" and "user.contact.email"
 * setFormData(form, data);
 *
 * @example
 * // Using with simple arrays using [] notation
 * const form = document.querySelector('form');
 * const data = {
 *   hobbies: ['Reading', 'Cycling', 'Cooking']
 * };
 * // Form has multiple fields with names like "hobbies[]"
 * setFormData(form, data);
 *
 * @example
 * // Using with array of objects using numeric indexers
 * const form = document.querySelector('form');
 * const data = {
 *   users: [
 *     { name: 'John', email: 'john@example.com' },
 *     { name: 'Jane', email: 'jane@example.com' }
 *   ]
 * };
 * // Form has fields with names like "users[0].name", "users[1].email", etc.
 * setFormData(form, data);
 *
 * @example
 * // Populating a <select> from context using the name convention
 * // <select name="country"></select>
 * setFormData(form, { country: 'se' }, {
 *   country: [
 *     { value: 'se', text: 'Sweden' },
 *     { value: 'us', text: 'United States' }
 *   ]
 * });
 *
 * @example
 * // Using data-source with custom value/text properties
 * // <select name="country" data-source="countries(id, name)"></select>
 * setFormData(form, { country: 2 }, {
 *   countries: [
 *     { id: 1, name: 'Sweden' },
 *     { id: 2, name: 'United States' }
 *   ]
 * });
 *
 * @example
 * // data-source as a method on context
 * // <select name="country" data-source="getCountries"></select>
 * setFormData(form, { country: 'se' }, {
 *   getCountries: () => [
 *     { value: 'se', text: 'Sweden' },
 *     { value: 'us', text: 'United States' }
 *   ]
 * });
 *
 * @example
 * // Grouping options into <optgroup> using a third field in data-source
 * // <select name="country" data-source="countries(id, name, region)"></select>
 * setFormData(form, { country: 2 }, {
 *   countries: [
 *     { id: 1, name: 'Sweden', region: 'Europe' },
 *     { id: 2, name: 'United States', region: 'Americas' },
 *     { id: 3, name: 'Germany', region: 'Europe' }
 *   ]
 * });
 * // Produces two <optgroup> elements, "Europe" and "Americas", in the
 * // order each group first appears in the items array.
 */
export declare function setFormData(form: HTMLFormElement, data: object, context?: object): void;