http://awwx.ws/encodequery0.arc:
(def encodequery (kvs) (tostring (between (k v) kvs (pr "&") (pr k "=" (urlencode:string v)))))
arc> (encodequery '((a "0 = 1 & 0") (b "foo"))) "a=0+%3D+1+%26+0&b=foo"
Same as Arc.