how to do isset function for new custom hook

[aaront1]

Hi,

 

I am able to add and display a hook using the following line

{hook h="DisplayProductTabArticle"}  

 

but how can I set an isset function around it?

so that that hook will only display when there is content, and when there is no content, I want to display something else.

 

i have tried the following, but it is always go to the else statement.

{if isset(DisplayProductTabArticle)}

 

or

 

{if isset($HOOK_DISPLAY_PRODUCT_TAB_ARTICLE)}