October 2018 1HaskellADay Problems and Solutions

• October 31st, 2018: A Happy Halloween arithmetic puzzle for you Happy Haskellers! 
• October 25th, 2018: Thursday's #haskell problem we have a (Loopful) compiler for BF* Thursday's #haskell solution: A BF* compiler, blocks of code in loops working. 
• October 24th, 2018: Wednesday's #haskell problem: Thus we enter the Turing Tarpit! The solution to Wednesday's #haskell problem is a BF* (loopless) interpreter that prints out "Hello, world!" I didn't think I could reach the pinnacle of programming in my lifetime, yet, here I am. 😎 
• October 19th, 2018: For Friday's #haskell problem we look at patterns in how people define categories: a little knowledge management. 
  
• October 17th, 2018: For Wednesday's #haskell problem we are using Haskell to automate writing a set of SQL INSERT statements. The function addDays to Wednesday's #haskell problem's rescue! 
  
• October 15th, 2018: Monday's #haskell problem is a little asset shell-game. A little Set.union, a little Set.difference, to get today's #haskell solution. 
• October 9th, 2018: Tuesday's #haskell problem: given a set of ids and our knowledge store from yesterday, determine the status of the new ids. Tuesday's #haskell solution: a Set to determine membership, and a Map to give the result, with a little bit of Frege-logic for fun! 
• October 8th, 2018: Monday's #haskell problem is random screening (okay: predetermined screening). Monday's #haskell solution: indexing into a list often? Consider the Array-type. 
• October 5th, 2018: Friday's #haskell problem we create a workflow to process chunks of files as SQL INSERT statements. And lo! and behold! A #haskell solution to all our problems... or today's problem, anyway. 
  

August 2018 1HaskellADay problems and solutions

• August 22nd, 2018: For Wednesday's #haskell problem we query a directory and massage some JSON: all in a day's work. Wednesday's #haskell solution: Processing JSONs ... LIKE A BOSS! 
• August 20th, 2018: For Monday's #haskell problem we distill UUIDs encoded in news media URLs. Monday's #haskell solution uses the break function FTW! 
• August 16th, 2018: For Thursday's #haskell problem we have Zipf's Law and words-in-sentences: a [The Current Year] analysis. 
• August 15th, 2018: For Wednesday's #haskell problem, we look at the 5000 most frequently used English words and do a bit of analysis. Wednesday's #haskell solution gets us the top 5000 English language words and their counts. 
• August 3rd, 2018: For Friday's #haskell problem we ingest JSON to discover its structure. 

July 2018 1HaskellADay Problems and Solutions

• July 31st, 2018: Tuesday's #haskell problem: let's start to build a #kakuro-solver! YES! (Image via http://www.menneske.no/kakuro)

• July 30th, 2018: For Monday's #haskell problem we are looking at merging databases. Monday's #haskell solution is a Set.intersection, and we see the shared data tables of the two databases. 
• July 24th, 2018: For Tuesday's #haskell problem we are discovering a JSON dictionary structure and pruning away non-entries. A little JSON dictionary exploration with #haskell gets us to our solution today. 
• July 17th, 2018: For Tuesday's #haskell problem we parse bits o' data from more extensive JSON.
• July 11th, 2018: Wednesday's #haskell problem is going from an 'iffy' JSON structure to PERFECT (well: less 'iffy') JSON structure. 
• July 10th, 2018: For Tuesday's #haskell problem we explore and structure illtempered JSON. When JSON looks normal, but it's not quite, you call ... AESON on wings of eagles for Tuesday's #haskell solution. 
• July 9th, 2018: In Monday's #haskell problem we discover structure in mondo JSON. Monday's #Haskell solution revealed itself in the first 300 characters of prettiness! 
• July 3rd, 2018: For Tuesday's #haskell problem we translate the graph-like JSON to a set of relations, viewable in a graph database.  For Tuesday, #haskell's graph-solution using Relation values and, ooh! pretteh pictures! 
  

June 2018 1HaskellADay Problems and Solutions

• June 29th, 2018: Friday's #haskell problem is partially parsing a very large file. For Friday's #haskell solution we parse a JSON map by hand. 
• June 27th, 2018: In Wednesday's #haskell problem, we parse JSON ... TWICE! to get to the underlying graph structure. Wednesday's #haskell solution is a little bit (a lot, actually) of JSON parsing, and then some graph analysis.
• June 26th, 2018: Tuesday #haskell problem converts a .properties file to JSON to make a REST call. Converting a .properties file to JSON in 23,952 easy steps for Tuesday's #haskell solution. 
• June 25th, 2018: Monday's #haskell problem is parsing a JSON error report and updating the JSON with new information. In Monday's #haskell solution, we get a little 'lens-y' to update JSON data. 
• June 22nd, 2018: Friday's #haskell problem sends articles-as-JSON to an AWS Lambda function for processing. 
• June 20th, 2018: Wednesday's #haskell problem is SymbolTable from a set of articles, then document vectors. 
• June 19th, 2018: We find out that 'materially' is the word for Tuesday's #haskell problem. For Tuesday's #haskell solution we find that parsing JSON is simpler than parsing TSV. This comes as a surprise to no one but me. 
• June 18th, 2018: Monday's #haskell problem asks: "When are unique IDs not unique IDs?" More dater-analyses. Monday's #haskell solution: we go from 2300+ duplicates to 30+ duplicates. A good day's work. 
• June 15th, 2018: Friday's #haskell problem is sorting and removing duplicatesfrom a data table by defining Ord. Friday's #haskell solution removes duplicate articles by ID... but are the articles duplicates? Hmmmm! 
• June 8th, 2018: "Dater-analytics" is the name of the game for Friday's #haskell problem. You get some real-world dater that's yucky, and you get to unyuckify it. You're welcome. 
• June 6th, 2018: Now we take that restructured JSON (see yesterday's exercise) and store that JSON in a PostgreSQL database for Wednesday's #haskell exercise. Wednesday's #haskell solution populates entities with wikipedia reference into a PostgreSQL database. 
  
• June 5th, 2018: Tuesday's #haskell problem is to transform 'pancake' JSON into ... '3-layer cake'-JSON? Sure. #nailedit Tuesday's #haskell solution we restructured JSON and saved result to ... JSON! YAY! 
• June 4th, 2018: Monday's #haskell problem: interlanguage communication via the function main. 3 + 4 = 7 ... now do that and have Python talking to Haskell. 

May 2018 1HaskellADay Problems and Solutions

• May 31st, 2018: In Thursday's #haskell problem we are analyzing JSON so we can produce ... MORE JSON! And thus grows our Big Data. Thursday's #haskell solution shows us the results of Big Data analytics? More Big Data. YES! 
• May 30th, 2018: Wednesday's #haskell problem we process 'big-ish' data. Wednesday's #haskell solution: You take your big(-ish) data, and you chart it. THIS WE CALL DATA SCIENCE! 
  
• May 25th, 2018: Friday's #haskell problem is load testing a web application with a database pull. Friday's #haskell solution: a load-tester in Haskell! AHA! 😎
• May 24th, 2018: Thursday's #haskell exercise is adding articles to be cleaned up, post-ETL, to a dirty table in PostgreSQL. Thursday's #haskell solution stages articles loaded into the database to be cleaned up later. 
  
• May 21st, 2018: Monday's #haskell problem is to insert NEW (triaged) articles into a PostgreSQL database. 
• May 18th, 2018: Friday's #haskell exercise: there seems to be a lot of tagged terms for articles. Download these terms-as-JSON from a REST endpoint and count them is today's exercise. Friday's #haskell solution has got me singing "Havana-na-na-na!" ... no, wait: I meant: "uploading tags from a REST endpoint to a PostgreSQL database." That's what I meant. 
• May 17th, 2018: Thursday's #haskell exercise is to add database update functionality to existing code and in a Writer/IO monad; yikes! Thursday's #haskell solution: from the triaged articles, the update SQL statements naturally fall out. 
• May 11th, 2018: Friday's #haskell exercise: bridging Python and Haskell to deliver a polyglot system. 
• May 8th, 2018: Tuesday's #haskell problem uses articles fetched from a REST endpoint and article metadata to triage articles for daily upload to a PostgreSQL database. Tuesday's #haskell solution... triage: get! 
• May 7th, 2018: Monday's #haskell problem is extracting metadata for articles stored in a PostgreSQL database. Monday's #haskell solution repurposes a library to fetch article metadata from a new article database. 
  
• May 4th, 2018: For Friday's #haskell problem we look at a daily upload process from a REST endpoint to a SQL data store and start to implement it. Friday's #haskell solution gets a week's worth of data from the REST endpoint. 

April 2018 1HaskellADay Problems and Solutions

• April 25th, 2018: For Wednesday's #haskell problem we prove, definitively, @fermatslibrary n^5 is n ... for very small n. For Wednesday's #haskell solution we learn that number theory is so cool! 
  
• April 24th, 2018: For Tuesday's #haskell problem we look for a fix-point of simplifying HTML. Good thing it's not NP-hard! ... no ... wait. Tuesday's #haskell solution is the fix-point for HTML. Just like the fix-point for factorial. Structurally, maybe, but otherwise, kinda not. 
• April 23rd, 2018: What happens when things go wrong? We start to look at debugging for Monday's #haskell problem. For Monday's #haskell solution: the error is not here; the error is in another castle. 
  
• April 20th, 2018: Friday's #haskell problem is to decode HTML entities from titles of articles. Friday's #haskell solution: deHTMLification: get 
• April 18th, 2018: Hey! Let's store the raw JSON as a fall-back should our ETL process fail for Wednesday's #haskell problem. Wednesday's #Haskell solution: storing raw JSON in a SQL data store BECAUSE WE CAN! 
  
• April 17th, 2018: For Tuesday's #haskell problem we upload articles from a different publisher of a compressed JSON archive with a different format. We find adding a differently-structured set of articles to IxArt store is simple for Tuesday's #haskell solution. 
• April 16th, 2018: For Monday's #haskell problem, we take articles-as-json from various sources and put them into a common SQL data store. For Monday's #haskell solution we upload articles from different publications to a common SQL data store, both compressed and uncompressed archives. 
  
• April 13th, 2018: Friday's #haskell problem is to grab packets of articles from a REST endpoint for later processing. Friday's #haskell solution: Those are some rather large packets downloaded from the REST endpoint! 
• April 12th, 2018: Thursday's #haskell problem: auditing and logs. Thursday's #haskell solution is to wrap packet extraction and insertion in an ETL process. 
  
• April 11th, 2018: Wednesday's #haskell problem: when we download packets of articles, let's record that event. Wednesday's #haskell solution: we're inserting packets into our new database. 
  
• April 10th, 2018: Tuesday's #haskell problem: 🎵 "Does anybody know what time it is?" 🎶 (bonus: name that tune) Tuesday's #haskell solution: "Hey, Mister! You got the time?" 
• April 9th, 2018: Monday's #haskell problem is to extract article tags from JSON then store them in a PostgreSQL lookup table. Monday's #haskell solution: Inserting tags for articles into a PostgreSQL database is a breeze! 
  
• April 6th, 2018: Friday's #haskell problem is to parse categories-as-JSON, strip it down to its essentials, and store in a PostgreSQL data table. Friday's #haskell solution uploaded categories to a PostgreSQL databse after 'removing the stupid.' That's a technical term. 
  
  
• April 5th, 2018: Thursday's #haskell problem is revising the database connector now that we're managing multiple databasen. Thursday #haskell solution is making connections to SQL databases configurable. Whoa. Edgy, tweeps! I'm really pressing the bleeding edge of technological advancement here with configurations and database connections. 
• April 4th, 2018: Wednesday's #haskell problem is storing authors in a PostgreSQL table. Wednesday's #haskell solution shows that transferring authors from articles to a SQL database is as easy as 1, 2, 3! 
  
  
• April 3rd, 2018: Tuesday's #haskell exercise: AUTHOR! AUTHOR! Is there an author in the house? Tuesday's #haskell solution: extracting author information from very unstructured data. 
• April 2nd, 2018: Monday's #haskell problem is to explore JSON to find the structure in the data. Monday's #haskell solution: oooh! Pritteh JSON! But what's this weirdness with the author-identifier? 
  

February 2018 1 Liner 1HaskellADay Problems and Solutions

• February 8th, 2018: We have maybe :: b -> (a -> b) -> Maybe a -> b. But we don't have list? Or do we? Define list:
  list :: b -> ([a] -> b) -> [a] -> b
  list nullanswer flist lst = undefined
• BONUS: Both Maybe a and [a] are binary types, ... so is MonadPlus:
  
  Maybe a = Nothing | Just a
  List a = Cons a (List a) | Nil
  MonadPlus m => mzero | m a `mplus` m a
  
  Is there some generalization that maybe and list are functions of? What is that generalization?
• February 6th, 2018:
  You have f :: a -> [b] -> [c]
  But instead of just one a you have [a]
  Define g :: [a] -> [b] -> [c]
  in terms of f
• Daniel @leptonyu g as bs = foldl (\xs a -> f a bs ++ xs) [] as
• ptdr_bot @m0rth0n g as bs = flip f bs =<< as
• Victoria C @ToriconPrime g as bs = concat $ fmap ($ bs) (fmap f as)
• matt @themattchan g = flip $ concatMap . flip f
• Nicoλas @BeRewt g = flip (flip (>>=) . flip f) Or: g as bs = as >>= flip f bs
• Sangeet Kar @sangeet_kar g = foldMap f