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POTrying to make the wireworld move by fmap (transition) but it shows me an error somehow (Haskell)
 

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  1. POTrying to make the wireworld move by fmap (transition) but it shows me an error somehow (Haskell)
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    <p>The same as my last question, im asked to make a wireworld by ordered lists, So i have written the following codes,(all of the function in the code is somehow defined in other modules, so, dont worry about that XD, feel free to ask me if u want to have a look at those "predefined funcs") however when i run it on terminal, it shows a error, here is the code:</p> <pre><code>module Transitions.For_Ordered_Lists_2D ( transition_world -- :: Ordered_Lists_2D Cell -&gt; Sparse_Line Cell ) where import Data.Cell (Cell (Head, Tail, Conductor, Empty)) import Data.Coordinates import Data.Ordered_Lists_2D -- Replace this function with something more meaningful: xandy :: Element_w_Coord Cell -&gt; Coord xandy (e, (x, y)) = (x, y) transition_sc :: Ordered_Lists_2D Cell -&gt; Placed_Elements Cell -&gt; Sparse_Line Cell transition_sc world pec = case world of Sparse_Line{y_pos = y, entries = xline}: rest_of_sparse_lines -&gt; case pec of Placed_Element{x_pos = x, entry = Head} : rest_of_placed_elements -&gt; (Sparse_Line{y_pos = y, entries = Placed_Element{x_pos = x, entry = Tail} : rest_of_placed_elements}) Placed_Element{x_pos = x, entry = Tail} : rest_of_placed_elements -&gt; (Sparse_Line{y_pos = y, entries = Placed_Element{x_pos = x, entry = Conductor} : rest_of_placed_elements}) Placed_Element{x_pos = x, entry = Empty} : rest_of_placed_elements -&gt; (Sparse_Line{y_pos = y, entries = Placed_Element{x_pos = x, entry = Empty} : rest_of_placed_elements}) Placed_Element{x_pos = x, entry = Conductor} : rest_of_placed_elements |element_occurrence Head neighbours == 1 || element_occurrence Head neighbours == 2 -&gt; (Sparse_Line{y_pos = y, entries = Placed_Element{x_pos = x, entry = Head} : rest_of_placed_elements}) |otherwise -&gt; (Sparse_Line{y_pos = y, entries = Placed_Element{x_pos = x, entry = Conductor} : rest_of_placed_elements}) where neighbours = local_elements (xandy (Conductor, (x, y))) world transition_world :: Ordered_Lists_2D Cell -&gt; Ordered_Lists_2D Cell transition_world world = fmap (transition_sc world) world --the end --the end --the end </code></pre> <p>however it shows me the following error:</p> <pre><code>u5363876@n114lt20:~/Desktop/lalal$ ./make_Wireworld [10 of 20] Compiling Transitions.For_Ordered_Lists_2D ( Sources/Transitions/For_Ordered_Lists_2D.hs, x86_64/Transitions/For_Ordered_Lists_2D.o ) Sources/Transitions/For_Ordered_Lists_2D.hs:35:53: Couldn't match expected type `Placed_Elements Cell' with actual type `Sparse_Line Cell' Expected type: [Placed_Elements Cell] Actual type: Ordered_Lists_2D Cell In the second argument of `fmap', namely `world' In the expression: fmap (transition_sc world) world </code></pre> <p>Im totally confused by this error Thank you in advance for anyone who can help me.</p> <p>@dave4420 here is the definition for Placed_Elements and Sparse_Lines</p> <pre><code>type Ordered_Lists_2D e = [Sparse_Line e] data Sparse_Line e = Sparse_Line {y_pos :: Y_Coord, entries :: Placed_Elements e} data Placed_Element e = Placed_Element {x_pos :: X_Coord, entry :: e} type Placed_Elements e = [Placed_Element e] </code></pre>
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    1. COShow us the definitions of `Placed_Elements` and `Sparse_Line`.
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      1. POTrying to make the wireworld move by fmap (transition) but it shows me an error somehow (Haskell)
      1. USdave4420
    2. COPlease ensure you copy+paste both your code and the error message into your question. There are details of the error message that suggest you have retyped the error message (inaccurately) instead of copying+pasting. Perhaps the code in your question is not the code you tried to compile, either. And then how can we help you?
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      1. POTrying to make the wireworld move by fmap (transition) but it shows me an error somehow (Haskell)
      1. USdave4420
    3. CO@dave4420, i have added it into my question, check it out XD
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      1. POTrying to make the wireworld move by fmap (transition) but it shows me an error somehow (Haskell)
      1. USlibra
 

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