To split a string by "\n" (newline character) in Haskell, you can use the lines function. The lines function takes a string and returns a list of strings broken at newline characters. Here is an example:
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import Data.List.Split main :: IO () main = do let str = "Hello\nworld\nHow are you?" let splitStrings = lines str print splitStrings |
Output:
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["Hello","world","How are you?"]
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In this example, the string "Hello\nworld\nHow are you?" is split into a list of strings using the lines function. The resulting list splitStrings contains three elements: "Hello", "world", and "How are you?".
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How to split a text block into words using whitespace in Haskell?
To split a text block into words using whitespace in Haskell, you can use the words function. Here's an example:
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import Data.List (words) main :: IO () main = do let text = "Hello world! This is a text block." wordsList = words text print wordsList |
The words function from Data.List takes a string as input and splits it into a list of words using whitespace characters as separators. In the example above, the text variable holds the text block, and wordsList will contain the list of words extracted from the text block using the words function.
Output:
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["Hello","world!","This","is","a","text","block."]
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You can then perform any desired operations on the wordsList variable or iterate through it to process each word as needed.
How to divide a sentence into a list of words in Haskell?
To divide a sentence into a list of words in Haskell, you can make use of the words function from the Prelude module. Here's an example:
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import Prelude hiding (words) divideIntoWords :: String -> [String] divideIntoWords sentence = words sentence |
In the code above, the divideIntoWords function takes a String parameter sentence and uses the words function to split it into a list of words. The words function has the following type signature: words :: String -> [String].
Here's an example usage:
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main :: IO () main = do let sentence = "Hello, how are you?" let wordsList = divideIntoWords sentence print wordsList |
Output:
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["Hello,","how","are","you?"]
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In this example, the input sentence is "Hello, how are you?", and the output is ["Hello,","how","are","you?"], where each word is an element in the list.
What is the technique to extract separate sentences from a string in Haskell?
There are multiple techniques to extract separate sentences from a string in Haskell. Here's one possible approach:
One way to extract separate sentences from a string is by using regular expressions. Haskell provides regular expression support through the regex-tdfa package. To use this package, you'll need to install it by running cabal install regex-tdfa.
Here's an example implementation using regular expressions to extract sentences from a string:
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import Text.Regex.TDFA extractSentences :: String -> [String] extractSentences text = getAllTextMatches (text =~ "([^.!?]+[.!?])" :: AllTextMatches [] String) |
In this implementation, the extractSentences function takes a string as input and returns a list of sentences. It uses the =~ operator from the regex-tdfa package to match the regular expression pattern "([^.!?]+[.!?])", which looks for one or more characters that are not periods, question marks, or exclamation marks, followed by a period, question mark, or exclamation mark. The getAllTextMatches function extracts all the matched sentences from the input string.
Here's an example usage of the extractSentences function:
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main :: IO () main = do let text = "This is sentence one. This is sentence two! Sentence three? Sentence four." let sentences = extractSentences text mapM_ putStrLn sentences |
Output:
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This is sentence one. This is sentence two! Sentence three? Sentence four. |
Note that this regular expression-based approach assumes that sentences end with periods, exclamation marks, or question marks, and that there are no abbreviations or other constructs that use these punctuation marks within a sentence. Depending on your specific requirements, you may need to adjust the regular expression pattern accordingly.
