Example in tutorial broken?

[tommythorn]

EDIT: Thanks for a making this. It looks really great.

I was trying to follow the examples in the tutorial, but it seems to not work:

$ cat MAC.hs
module MAC where

import Clash.Prelude
import Clash.Explicit.Testbench

ma acc (x,y) = acc + x * y

macT acc (x,y) = (acc',o)
  where
    acc' = ma acc (x,y)
    o    = acc

mac = mealy macT 0

topEntity
  :: Clock System Source
  -> Reset System Asynchronous
  -> Signal System (Signed 9, Signed 9)
  -> Signal System (Signed 9)
topEntity = exposeClockReset mac
{-# NOINLINE topEntity #-}

testBench :: Signal System Bool
testBench = done
  where
    testInput    = stimuliGenerator clk rst $ (listToVecTH [(1,1) :: (Signed 9,Signed 9),(2,2),(3,3),(4,4)])
    expectOutput = outputVerifier clk rst $(listToVecTH [0 :: Signed 9,1,5,14])
    done         = expectOutput (topEntity clk rst testInput)
    clk          = tbSystemClockGen (not <$> done)
    rst          = systemResetGen

$ clashi MAC.hs 
CLaSHi, version 0.99 (using clash-lib, version 0.99):
http://www.clash-lang.org/  :? for help
[1 of 1] Compiling MAC              ( MAC.hs, interpreted )

MAC.hs:26:48: error:
    • Couldn't match type ‘Language.Haskell.TH.Syntax.Q
                             Language.Haskell.TH.Syntax.Exp’
                     with ‘Vec l0 (Signed 9, Signed 9)’
      Expected type: Vec l0 (Signed 9, Signed 9)
        Actual type: Language.Haskell.TH.Lib.Internal.ExpQ
    • In the second argument of ‘($)’, namely
        ‘(listToVecTH
            [(1, 1) :: (Signed 9, Signed 9), (2, 2), (3, 3), (4, 4)])’
      In the expression:
        stimuliGenerator clk rst
          $ (listToVecTH
               [(1, 1) :: (Signed 9, Signed 9), (2, 2), (3, 3), (4, 4)])
      In an equation for ‘testInput’:
          testInput
            = stimuliGenerator clk rst
                $ (listToVecTH
                     [(1, 1) :: (Signed 9, Signed 9), (2, 2), (3, 3), ....])
   |
26 |     testInput    = stimuliGenerator clk rst $ (listToVecTH [(1,1) :: (Signed 9,Signed 9),(2,2),(3,3),(4,4)])
   |                                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Failed, no modules loaded.

[christiaanb]

In the line:

testInput    = stimuliGenerator clk rst $ (listToVecTH [(1,1) :: (Signed 9,Signed 9),(2,2),(3,3),(4,4)])

there is a space between $ and ( which is causing the error. The issue is that $( ... ) is a special type of bracket which inserts a compile-time generated AST into the code, which is called Template Haskell: https://downloads.haskell.org/~ghc/8.4.3/docs/html/users_guide/glasgow_exts.html#template-haskell

To fix, change the line to:

testInput    = stimuliGenerator clk rst $(listToVecTH [(1,1) :: (Signed 9,Signed 9),(2,2),(3,3),(4,4)])

Did you get this error from copy/pasting the code? If so, which OS are you using? because on my Linux machine copy/pasting the code from: http://hackage.haskell.org/package/clash-prelude-0.99.1/docs/Clash-Tutorial.html#g:7 doesn't result in a space between $ and (

[tommythorn]

oops. I reformatted the line and when it didn't work reverted my change, incompletely it would seem. Sorry and thanks.