constructor( cacheKey ) {

		/**
		 * The pipeline's cache key.
		 *
		 * @type {string}
		 */
		this.cacheKey = cacheKey;

		/**
		 * How often the pipeline is currently in use.
		 *
		 * @type {number}
		 * @default 0
		 */
		this.usedTimes = 0;

	}
Constructs a new pipeline.

@param {string} cacheKey - The pipeline's cache key.