Custom functions - type signatures

Questions and Answers
1

I had the following functions working:

let drumMappings = [("b","c3"),("s","cs3"),("sl","d3"),("sr","f3"),("st","fs3"),("hp","c4"),("hpo","b4"),("hc","d4"),("hhc","e4"),("hb","f4"),("hho","fs4"),("hho1","g4"),("hho2","gs4"),("ho","a4"),("hob","as4"),("r","c5"),("rb","cs5"),("rc","d5"),("rm","ds5"),("t1","b5"),("t2","a5"),("t3","g5"),("t4","f5"),("c1","f6"),("c1m","fs6"),("c2","g6"),("c2m","gs6"),("ch","a6"),("chm","as6"),("sp","f7"), ("w","c8"), ("conga", "b3")]
    dMap notes = (inhabit drumMappings notes)
    drumChannel = 0
    d myNotes myAmp = d1 $ n (dMap myNotes) #s "midi" #midichan drumChannel #amp myAmp

which let me send MIDI to a drum VST with less typing

d "b s hho" 0.5

instead of

d1 $ n "c3 cs3 fs4" #s "midi" #midichan 0 #amp 0.5

I want to specify the pattern number with a new parameter (i.e. not always $d1). I got this:

d myPatternNumber myNotes myAmp = p myPatternNumber $ n (dMap myNotes) #s "midi" #midichan dChannel #amp myAmp

However, if I try

d 1 "b s hho" 0.5

I get an error:

Warning: GHCi | 
Warning: GHCi | <interactive>:5577:1: error:
Warning: GHCi |     * Could not deduce (Num t0)
Warning: GHCi |       from the context: (Num t, Num (t -> Pattern ValueMap -> b))
Warning: GHCi |         bound by the inferred type for `it':
Warning: GHCi |                    forall {t} {b}. (Num t, Num (t -> Pattern ValueMap -> b)) => b
tidal> Warning: GHCi |         at <interactive>:5577:1-17
Warning: GHCi |       The type variable `t0' is ambiguous
Warning: GHCi |       Potentially matching instances:
Warning: GHCi |         instance Integral a => Num (Ratio a) -- Defined in `GHC.Real'
Warning: GHCi |         instance Num Note -- Defined in `Sound.Tidal.Pattern'
Warning: GHCi |         ...plus 7 others
Warning: GHCi |         ...plus 33 instances involving out-of-scope types
Warning: GHCi |         (use -fprint-potential-instances to see them all)
Warning: GHCi |     * In the ambiguity check for the inferred type for `it'
Warning: GHCi |       To defer the ambiguity check to use sites, enable AllowAmbiguousTypes
Warning: GHCi |       When checking the inferred type
Warning: GHCi |         it :: forall {t} {b}.
Warning: GHCi |               (Num t, Num (t -> Pattern ValueMap -> b)) =>
Warning: GHCi |               b

Any ideas on how to implement this? Thanks!

2

FWIW, I briefly tried your functions yesterday and was unable to reproduce the issue.

3

One question: what version of Tidal are you using?

4

Thanks for trying it out! I'm using 1.9.2. What version are you using?

5

1.9.2 as well.

6

Though these things really shouldn’t have an impact, I might as well also ask: what GHC version are you running? (9.4.2 here, which reminds me that I should soon install some updates.)

7

I've just reinstalled tidal with chocolatey. Now I'm getting errors with qtrigger; has that happened to anyone?

8

Yes, it's likely due to this change: https://github.com/tidalcycles/Tidal/pull/970

9

Yes you don't need to specify the pattern id any more Trigger a pattern from the start | Tidal Cycles