另一种解决方案是使用package_facts模块，如下所示：

- hosts: localhost
  tasks:
    - package_facts:

    - debug:
        msg: "Nginx is installed!"
      when: "'nginx' in packages"

但您也可以为两个任务注册单独的变量，然后合并结果：

- hosts: localhost
  tasks:
    - name: Veryfying nginx installation # RedHat
      command: "rpm -q nginx"
      when: ansible_facts.pkg_mgr in ["yum","dnf","rpm"] #or (ansible_os_family == "RedHat")
      failed_when: false
      register: rpm_check

    - name: Veryfying nginx installation # Debian
      command: "dpkg -l nginx"
      when: ansible_facts.pkg_mgr in ["dpkg", "apt"] #or (ansible_os_family == "Debian")
      failed_when: false
      register: dpkg_check

    - set_fact:
        nginx_result: >-
          {{
          (rpm_check is not skipped and rpm_check.rc == 0) or
          (dpkg_check is not skipped and dpkg_check.rc == 0)
          }}

    - debug:
        msg: "nginx is installed"
      when: nginx_result