Method append

packages/common/http/src/headers.ts:144–146

* Appends a new value to the existing set of values for a header * and returns them in a clone of the original instance. * * @param name The header name for which to append the values. * @param value The value to append. * * @returns A clone of the HTTP headers object with the valu

(name: string, value: string | string[])

   */

  append(name: string, value: string | string[]): HttpHeaders {
    return this.clone({name, value, op: 'a'});
  }
  /**
   * Sets or modifies a value for a given header in a clone of the original instance.
   * If the header already exists, its value is replaced with the given value