Find length of slice

I’m trying to make a random selection out of several possible directories of content. On the homepage there will be a link to this. On a jekyll version of the same site I used to do this using the liquid templating language so now I’m trying it in the hugo way. What I have is:
{{ $hughku := slice }}
{{ $hughku = $hughku | append slice }}
{{ $hughku = $hughku | append slice }}
{{ len $hughku }}

This ‘len’ gives ‘7’ which looks like the number of characters rather than the couple of hundred maps that are in there. I can range over $hughku and see all the maps in there. What is needed is the count so that I can then generate a random number not bigger than it and then get that index out of the array as the winner selection. Am I going about this the wrong way, or what?

Difficult to say without seeing the structure of your data directory, and the contents of the data files.

When I give it a:
{{ range $hughku }}
{{ print . }}
{{ end }}
I get:
[map[title:title1 url:/link1] map[title:title2 url:/link2] etc…