code: function fromCache(options) {
    var filename = options.filename;
    if (options.cache) {
      if (filename) {
        if (cache[filename]) {
          return cache[filename];
        }
      }
      else {
        throw new Error('filename is required when using the cache option');
      }
    }
    return false;
  }
docs: Get a template from the cache
  
  @param {object} options
  @return {Function}