Erlog is an actively maintained option for using prolog from erlang. It's maintained by Robert Virding, who also maintains Lisp Flavored Erlang (lfe).
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fresleven
I think I may be more representative of the camp complaining about erlang's syntax. My background is as a sysadmin without CS training, with only prior experience using ruby, python, and shell scripting.
It took me about four months of hard studying for erlang to click. I think it was due to learning some CS fundamentals (e.g. had never heard of a tuple before, never seen multiple dispatch), learning functional programming fundamentals (had never used a purely functional language before - unless you count bash), and had never looked at prolog. Finally, I was simultaneously exposed to new concepts of concurrency, pattern matching, etc.
I think what happened was that the unusual syntax is the easiest thing to blame for the resulting confusion, because it's the surface layer you engage with.
Seeing a link to a gopher:// site and discovering that Safari in iOS still supports it made my day.