CODEWITHSUNDEEP
listfunctionhaskelltuples
sanic
sanic

Reputation: 2085

Haskell: Using Tuples and preexisting nested lists

So far I have these two functions:

splitLines :: String -> [[String]]
splitLines splitLinesStr = splitWords (lines splitLinesStr)

splitWords :: [String] -> [[String]]
splitWords splitWordStr = map words splitWordStr

Both work to aid in completing step 1-3. However I do not know how to how to create a tuple of an int and a list within a list (as stated by step 4). How would one go about doing this?

stage 1: the original input, for example,

"a&b b c.\na dd\n"

stage 2: the original input, split into a list of lines, as in

["a&b b c.", "a dd"]

stage 3: the list of lines, split further into a list of list of words, as in

[["a", "b", "b", "c"], ["a", "dd"]]

stage 4: the list of lists, "tupled" so that line numbers are attached to them, as in 

[(1,["a", "b", "b", "c"]), (2,["a", "dd"])]

stage 5: the list of words (all at the top level) where each is paired with its line number, as in

[(1,"a"), (1,"b"), (1,"b"), (1,"c"), (2,"a"), (2,"dd")]

Upvotes: 0

Views: 97

Answers (1)

duplode
duplode

Reputation: 34398

Hint 1: You can generate an infinite list of integer numbers with the following syntax:

[1..]

Hint 2: There is a function called zip with a very suggestive type:

zip :: [a] -> [b] -> [(a, b)]

Upvotes: 1

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