GIS -API manipulation.

[#1]

I have GIS map and in the popup content I have below Hyperlink (HTML)

           <a href="http://www.abc.com/en-us/insights/research-the-market#?Keyword='&[Market]&'&FilterTypes=Research" class="btn btn-info btn-xs" target="_blank"></a>

here Market is a column with different place and the link looks like below where Denver is one of the Market

http://www.abc.com/en-us/insights/research-the-market#?Keyword=Denver&FilterTypes=Research

Now I want to use the below hyperlink where Market should be replaced by [if(len(Cluster)<0,Market,Cluster)] where Cluster is another column with other places.

<a href="http://www.abc.com/en-us/insights/research-the-market#?Keyword='&[if(len(Cluster)<0,Market,Cluster))]&'&FilterTypes=Research" class="btn btn-info btn-xs" target="_blank"></a>

but that if is not working and the link looks like below

http://www.abc.com/en-us/insights/research-the-market#?Keyword=&FilterTypes=Research

Thanks much