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jamonathin

Wed Nov 08, 2006 12:23 pm


Miranda Character lists

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Hey all, im having trouble with this probelm where i have a phrase, and i need to break it down into a list of words.

I am able to remove punctuation and spaces so I'm just left with words, but I cant figure out how to put the words into a list.  Which would be a List of a List of characters.

I've spent endless hours, manipulating, trying different strategies, everything.

Here is my code where I can remove punctuation, and i know where the word is isolated, but not shure on how to do something with it.


word "" = ""
word (x:xs) = 

If you cant run it, here's a sample input and output:


"When I was a kid my favorite relative was Uncle Caveman. After school we'd all go play in his cave, and every once in a while he would eat one of us. It wasn't until later that I found out that Uncle Caveman was a bear."


WhenIwasakidmyfavoriterelativewasUncleCavemanAfterschoolwedallgoplayinhiscaveandeveryonceinawhilehewouldeatoneofusItwasntuntillaterthatIfoundoutthatUncleCavemanwasabear

Any help would be appreciated :)


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Lazy

Thu Nov 09, 2006 6:24 am



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I don't know Miranda... but here's a simple solution in Haskell. It can be vastly improved, but as it is, I think it demonstrates the concept well enough. I'm still only learning Haskell, so any constructive criticisms would be greatly appreciated.

import Data.Char

getWords [] = []
getWords s = if getFirst s == "" then getWords ( getRest s )
                                 else getFirst s : getWords ( getRest s )  
                 
                 where
	
                 suffix [] = []
                 suffix x  = tail x

                 getFirst s = takeWhile isWordChar s
                 getRest  s = suffix $ dropWhile isWordChar s 

                 isWordChar c = ( isLetter c ) || ( c == '\'')



EDIT: Haskell actually comes with a similar function, words, which splits [Char] into [[Char]] using whitespace as boundary.


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jamonathin

Thu Nov 09, 2006 12:04 pm



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And i dont know Haskell :lol:, but I did end up figuring it out and it is similar to the solution you gave me (which i appreciate you doing :)).

Here's the solution


get_words (x:xs) =