get(name) {
    if (!this.has_(name)) {
      throw new Error('Configuration ' + name + ' is not defined.');
    }
    return this.get_(name);
  }
Gets the configuration value for the given name. If an unrecognized name is
specified, an `Error` is thrown.

@param {string} name The name of the configuration.
@return {*|undefined} The configuration value.