March 2021 1HaskellADay 1Liners

• 2021-03-23:

  You have [a] and (a -> IO b).

  You want IO [(a, b)]

  That is, you want to pair your inputs to their outputs for further processing in the IO-domain.

  • Chris Martin @chris__martin:

    \as f -> traverse @ [] @ IO (\a -> f a >>= \b ->

    return (a, b)) as

  • cλementd Children crossing @clementd:

    traverse (sequenceA . id &&& f)

    (actually, tranverse (sequence . (id &&& f)))

    Or p traverse (traverse f . dup)

• 2021-03-23: You have

  [([a], [b])]

  You want ([a], [b])

  so: [([1,2], ["hi"]), ([3,4], ["bye"])]

  becomes ([1,2,3,4],["hi","bye"])

  • karakfa @karakfa:

    conc xs = (concatMap fst xs, concatMap snd xs)

March 2021 1HaskellADay Problems and Solutions

• 2021-03-31, Wednesday: Let's go on 50 last dates for today's #haskell problem. Today's #haskell solution shows us the fifty last dates were the fifty best dates. 
  
  
  
• 2021-03-30, Tuesday: Directorizin' ... WITH STYLE! ... is today's #haskell problem. Today's #haskell solution: BEHOLD THE MIGHTY POWER OF THE <*>! 
• 2021-03-29, Monday: Today's #haskell problem tackles plurality and connectives to list the contents of our Fruits Basket. Today's #haskell solution gives us fruits, in the basket, properly-speaking, thanks to George Boole. 
• 2021-03-25, Thursday: Today's #haskell problem has me FORTHing AT THE MOUTH! ... AGAIN! ... no, ... wait ... 
• 2021-03-23, Tuesday: Let's go FORTH! and conquer! for today's #haskell problem. Today's #haskell solution gives us a little FORTHer to go FORTH and FORTH! ... and also demonstrates Gauss' sum formula ... IN FORTH! ... which is nice. 
• 2021-03-22, Monday: Fixing-up and validating a JSON-as-string (and don't get me started) is today's #haskell problem. Today's #haskell solution uses Data.Aeson to transform some JSON, ... typefully. 
• 2021-03-19: pi. Not pie. Not tau. pi... you know, or: close enough, is served as today's #haskell problem (via @AnecdotesMaths). PI! for today's #haskell solution. And a pie recipe from Sumeria, if you're in a baking-mood. 
  
  
  
• 2021-03-18: Today's #haskell problem is to update lookup tables with new values. Today's #haskell solution gets the indices for foo, bar, quux, and ... Joe??? Okay. 
• 2021-03-16: Today's #haskell problem uses natural language processing to consolidate words in the cloud. et, voilà: Grace Hopper wikipedia entry word-cloud, trimmed and stemmed, for today's #haskell solution. 
  
  
  
• 2021-03-15: Today's #haskell problem explores Grace Hopper's wikipedia entry as a word-cloud generated by d3js.org for #WomensHistoryMonth Today's #haskell solution removed some obvious things (punctuation and citations) to simplify Grace Hopper's word-cloud. #WomenHistoryMonth
  
  
  
• 2021-03-11: It's not every Tom, Dick, and Harry that can do today's #haskell exercise...  In today's #haskell solution you want an id? YOU GOT AN ID! 😤 
• 2021-03-09: Let's query a directory and do something with each file in that directory for today's #haskell problem. Today's #haskell solution? THAT WAS EASY! ... so! What are we doing tomorrow? 😃 
• 2021-03-05: Today we're shell-scripting ... WITH HASKELL! 😤  Today's #haskell solution says: "Well, hello there, good lookin'!"  
• 2021-03-04: Today's #haskell problem: you have a time-series of values, not necessary gapless, get the latest value; then, get 'yesterday's' value. Today's #haskell solution gives us some useful functions to navigate a time-series of values. 
• 2021-03-03: Today's #haskell problem asks: "Where in the world are these wineries?" Then answers that question. Ooh! Wineries! Wineries all over the globe! is in today's #haskell solution. 
  
  
  
  
  
  
  
  
  
  
  
  
• 2021-03-02: For today's #haskell problem, let's add approved matched data to wineries in the graph-store. The #haskell solution! ... with a pic! 
  
  
  
• 2021-03-01: Today's #haskell problem approves matched wineries for (eventual) storage. We approve wiki-to-graph winery metaphone matches for today's #haskell solution.