a := "A"
b := "B"
c := "C"

a,b,c = c,b,a
say "A,B,C -> $a,$b,$c"
fail unless "$a,$b,$c" == "C,B,A"

strings := ["A","B"]

eval_log := [:String]
def log(msg:String):[String]
    eval_log.insert(msg)
    return strings

(log("lhs1"))[1], (log("lhs2"))[2] = (log("rhs1"))[2], (log("rhs2"))[1]

say "Access order: $eval_log"
say "Result: $strings"
fail unless "$strings" == "[B, A]"
fail unless "$eval_log" == "[lhs1, lhs2, rhs1, rhs2]"

eval_log := [:String]
queue := ["a","b","c","d"]
i := 1
def fresh(msg:String):String
    eval_log.insert(msg)
    ret := queue[i]
    i += 1
    return ret

table := {:String=String}
table[fresh("lhs1")], table[fresh("lhs2")] = fresh("rhs1"),fresh("rhs2")

say "$table"

fail "Eval log is wrong: $eval_log" unless "$eval_log" == "[lhs1, lhs2, rhs1, rhs2]"
fail "Table is wrong: $(table["a"]) $(table["b"])" unless table["a"] == "c" and table["b"] == "d"