issue with :left-join, missing ::expr-list spec

[mladvladimir]

Hi,
If I try to evaluate i.e.

(s/explain 
  ::left-join 
  '[:left-join 
    [:bgp [?s ?p ?o]]
    [:bgp [?s :rdf/type ?type]]
   true])

I've got:
Exception Unable to resolve spec: :arachne.aristotle.query.spec/expr-list clojure.spec.alpha/reg-resolve! (alpha.clj:69)

Probably in ::left-join spec need to put:

(s/cat :op #{:left-join} :left ::operation :right ::operation
         :exprs (s/+ ::expr)))

instead of:

(s/cat :op #{:left-join} :left ::operation :right ::operation
         :exprs (s/+ ::expr-list)))

Awesome lib, BTW! :)

Regards