How to convert (or cast) a pattern of Int to a pattern of Double

Questions and Answers
1

Haskell question: is it possible to cast a pattern of Int to a pattern of Double? Is there a nifty Tidal way to cast it?

Specifically, I want to cast a pattern produced by markovPat so that it can be used as the first argument in select:

let pat1 = "{1@3}%16"
    pat2 = "1(3,8)"
    pat3 = "1*8"
    mpat = markovPat 8 1 [[3,5,2], [4,4,7], [2,1,3]]

d1 $ struct (select (mpat / 2) [pat1, pat2, pat3]) $ s "bd"

The above code results in the error:

<interactive>:390:22: error:
    • Couldn't match type ‘Int’ with ‘Double’
      Expected: Pattern Double
        Actual: Pattern Int
    • In the first argument of ‘(/)’, namely ‘mpat’
      In the first argument of ‘select’, namely ‘(mpat / 2)’
      In the first argument of ‘struct’, namely
        ‘(select (mpat / 2) [pat1, pat2, pat3])’

If I use squeeze without the / 2 instead of using select, the idea works, but I would really prefer to use select instead.

Ideas?

2

Ah, fmap solves my issue, and is even better because then I can create my own mapping:

let pat1 = "{1@3}%16"
    pat2 = "1(3,8)"
    pat3 = "1*8"
    mpat = (fmap ([0,0.5,1]!!)) $ markovPat 8 1 [[3,5,2], [4,4,7], [2,1,3]]

d1 $ struct (select mpat [pat1, pat2, pat3]) $ s "bd"
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3

Chiming in just for reference: fromIntegral :: (Integral a, Num b) => a -> b can almost always get you where you need to go, ala fromIntegral <$> pat.

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