time command: add timeQuiet option

src/Cryptol/REPL/Command.hs

@@ -1016,17 +1016,20 @@ typeOfCmd str pos fnm = do
 timeCmd :: String -> (Int, Int) -> Maybe FilePath -> REPL ()
 timeCmd str pos fnm = do
   period <- getKnownUser "timeMeasurementPeriod" :: REPL Int
-  rPutStrLn $ "Measuring for " ++ show period ++ " seconds"
+  quiet <- getKnownUser "timeQuiet"
+  unless quiet $
+    rPutStrLn $ "Measuring for " ++ show period ++ " seconds"
   pExpr <- replParseExpr str pos fnm
   (_, def, sig) <- replCheckExpr pExpr
   replPrepareCheckedExpr def sig >>= \case
     Nothing -> raise (EvalPolyError sig)
     Just (_, expr) -> do
       Bench.BenchmarkStats {..} <- liftModuleCmd
         (rethrowEvalError . M.benchmarkExpr (fromIntegral period) expr)
-      rPutStrLn $ "Avg time: " ++ Bench.secs benchAvgTime
-           ++ "    Avg CPU time: " ++ Bench.secs benchAvgCpuTime
-           ++ "    Avg cycles: " ++ show benchAvgCycles
+      unless quiet $
+        rPutStrLn $ "Avg time: " ++ Bench.secs benchAvgTime
+             ++ "    Avg CPU time: " ++ Bench.secs benchAvgCpuTime
+             ++ "    Avg cycles: " ++ show benchAvgCycles
       let mkStatsRec time cpuTime cycles = recordFromFields
             [("avgTime", time), ("avgCpuTime", cpuTime), ("avgCycles", cycles)]
           itType = E.TVRec $ mkStatsRec E.tvFloat64 E.tvFloat64 E.TVInteger

src/Cryptol/REPL/Monad.hs

@@ -992,6 +992,9 @@ userOptions  = mkOptionMap
     , "This is a lower bound and the actual time taken might be higher if the"
     , "  evaluation takes a long time."
     ]
+
+  , simpleOpt "timeQuiet" ["time-quiet"] (EnvBool False) noCheck
+    "Suppress output of :time command and only bind result to `it`."
   ]