/**
 * An abstract class that defines a template rendering and compilation interface.
 *
 * Implementations of this class should provide specific logic for rendering
 * templates and compiling source code into strings.
 */
export declare abstract class TemplateEngine {
    protected abstract extension: string;
    /**
     * Renders a template with the provided data.
     *
     * @param template - The path to the file to read throw error if file now found.
     * @param data - Optional data to be used for rendering the template. The
     *               shape of this data depends on the specific implementation
     *               and the template being used.
     * @returns The rendered string resulting from applying the data to the template.
     */
    render(template: string, data?: object): Promise<string>;
    /**
     * Compiles source code into a string representation.
     *
     * @param source - A string representing the source code to be compiled.
     * @param data - Optional data that may be used during the compilation
     *               process. The specific use of this data depends on the
     *               implementation and the source code being compiled.
     * @returns The compiled string resulting from processing the source code.
     */
    abstract compile(source: string, data?: object): string;
    readFileToString(filePath: string): Promise<string>;
}