original_string: protected function check_plugin_is_installed(string $component) : Bool {
          if (!isset($this->checkedplugins[$component])) {
              $pluginmanager = \core_plugin_manager::instance();
              $plugin = $pluginmanager->get_plugin_info($component);
              $this->checkedplugins[$component] = !is_null($plugin);
          }
          return $this->checkedplugins[$component];
      }
code: protected function check_plugin_is_installed(string $component) : Bool {
          if (!isset($this->checkedplugins[$component])) {
              $pluginmanager = \core_plugin_manager::instance();
              $plugin = $pluginmanager->get_plugin_info($component);
              $this->checkedplugins[$component] = !is_null($plugin);
          }
          return $this->checkedplugins[$component];
      }
code_tokens: protected function check_plugin_is_installed ( string $ component ) : Bool { if ( ! isset ( $ this -> checkedplugins [ $ component ] ) ) { $ pluginmanager = \ core_plugin_manager :: instance ( ) ; $ plugin = $ pluginmanager -> get_plugin_info ( $ component ) ; $ this -> checkedplugins [ $ component ] = ! is_null ( $ plugin ) ; } return $ this -> checkedplugins [ $ component ] ; }
docstring: Check to see if a specified plugin is installed.
  
  @param  string $component The component name e.g. tool_log
  @return bool Whether this component is installed.
docstring_tokens: Check to see if a specified plugin is installed .