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copied!<p>run is of type String -> String, so you probably don't want the do notation[1]. I'd advise you to do this:</p> <ol> <li>comment out everything below the listDouble function, load that, and be sure that'll compile. </li> <li><p>add a test value that's formatted like the file you expect. Something like:</p> <pre><code> t = "[1,9]\n3\n1.0 1.0 1.0\n1.0 1.0 1.0\n1.0\n1.0" </code></pre></li> <li><p>add a test values that the top level for the values you're defining in run</p> <pre><code>ln = lines t seq = ln!!0 states = ln!!1 l1 = listDouble (ln!!2) l2 = listDouble (ln!!3) tr1 = readDouble (ln!!4) tr2 = readDouble (ln!!5) </code></pre></li> <li><p>use the type signature of scoreFunction to guide you in building the arguments to that function, then the rest of run, and finally main.</p></li> </ol> <p>Learn to use an interpreter, such as Hugs, ghci. Learn the :r and :t commands. For example (i'm using currying to give some but not all of a functions arguments): </p> <pre><code> :t scoreFunction :t scoreFunction "" :t scoreFunction 3445 </code></pre> <p>You can use this to have the system help you determine if you're on the right track. Doing this at the top level with introduce a conflict with a Prelude.seq function - either rename your seq, or refernence yours as Main.seq.</p> <p>Haskell is notorious for error messages that are inscrutable to beginners, so I'd recommend periodically rolling back to a version that compiles, either by commenting out your current experiments (which is what I had you do in step 1 above), or using your editors undo function.</p> <p>[1]I say probably because Strings, being lists of Characters, are instances of the Monad class, but that's fairly advanced </p>

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