On Tue, 29 Jan 2013 09:23:34 +0100, Casey Basichis wrote:

I guess what I'm looking for doesn't exist, which is what it is. I'm just interested in why it's not an ideal way to take in Haskell, starting with the common and moving to the to rare.

It is worth while to study the Prelude functions: A Tour of the Haskell Prelude http://undergraduate.csse.uwa.edu.au/units/CITS1211/Documentation/tourofprel... and: A tour of the Haskell Monad functions http://members.chello.nl/hjgtuyl/tourdemonad.html Regards, Henk-Jan van Tuyl -- http://Van.Tuyl.eu/ http://members.chello.nl/hjgtuyl/tourdemonad.html Haskell programming --

On Tue, Jan 29, 2013 at 1:53 PM, Casey Basichis wrote:

Hi Dmitry,

Thanks for the links. I've been through the 24 Days of Hackage, but I think its time to run through them again now that I'm a little more familiar with everything.

Why do you think browsing function by function is a bad idea? It seems that knowing exactly what the most used functions are would be an extremely effective way of finding both which parts of the Prelude and Hackage are most broadly useful (instead of browsing them like a phonebook) and also finding support from the community as the most commonly used functions would likely be the easiest to find support for.

Find out "the most used functions" seems to be eminently desirable. To do that we need to count function-uses. And to do that we need to know what to count. Do we? If you remember, the cost-centre mode of counting functions in haskell programs was precisely because the usual (first-order language) mode of counting would lead to the strange conclusion that map and foldr were the most used and therefore most inefficient functions in Haskell! So a new way of counting had to be devised. There is a book: Mathsemantics by Edward Macneal which deals with things like: How does an airline count the number of passengers. I quote from the book: I 1980 I was one passenger, ten passengers, eighteen passengers, thirty-six

passengers, forty-two passengers, fifty-five passengers, seventy-two passengers and ninety-four passengers. Each of these statements is true.

He then goes on to explain. I was one passenger in the sense that I was a person who traveled by air in

that year. I was eighteen passengers in the sense that I made eighteen round trips. I was forty-two passengers in the sense that on forty-two different occasions I entered and exited the system of a different carrier. I was seventy-two passengers in the sense that on seventy-two occasions I was on board an aircraft when it took off from one place and landed at another. I was ninety-four passengers in the sense that I made ninety-four separate entrances and exits from airport terminal buildings.

[He missed the explanation for 10!] He goes on to say that these differences are not mere technicalities and its important to get the sense of 'passenger' So… like 'passenger', how many meanings does 'function-use' have? Rusi -- http://www.the-magus.in http://blog.languager.org

One thing you could do is download Hackage (easy enough with a little scripting of 'cabal list'; see for example http://www.haskell.org/pipermail/haskell-cafe/2011-July/093669.html ), unpack, and use Language.Haskell.Exts to parse every Haskell file. Here are two examples from the past: 1. http://www.haskell.org/pipermail/haskell-cafe/2012-January/098618.html function-name search script which lets you parse a large number of source files and print out anything calling a specified function (eg. if you were thinking about deprecating something) 2. http://www.haskell.org/pipermail/haskell-cafe/2011-May/091663.html language-extension search script; I used it to see how many source files ever invoked LANGUAGE pragmas and which ones. -- gwern http://www.gwern.net

I just ordered Mathsemantics for a hefty $2.10. Your article's were an enjoyable read and very informative. I'll dig more into you blog tonight. I've read the Great Good book, Haskell school of music, and I'm working my way through Real World Haskell. I've also read countless blog articles on Haskell. With a great deal read and understood about Haskell I have no confidence that I can make anything in it at all. Kurt Vonnegut retyped James Joyce's work to feel a great novel under his fingers before writing his own. Webster knew English better than Shakespeare. Shakespeare was a master of creation. To be able to create from a small core and then extend those intuitions with knowledge over time is to me far more effective than mastering language and then attempting creation. While not rigorous, getting hands on with high level practical libraries and working by example would have built my intuitions far faster than all of the countless reading and toy examples I've done. The problem is, for that approach, there isn't any material for a book or insightful blog post to be written. Mimetics are mundane and unnecessary to those in the know. The teachers seem to be unaware of how their own intuitions were formed. While learning the fundamentals my mind struggles to imagine how these basic concepts play into the larger picture - how would they use foldr to build persistent? I don't have real answers to those questions but it's a constant distraction. I am certain that sitting down with a few simple examples of how to use a library like Persistent, without any concern as to how it works, will surely take me from a useless Haskeller to being able to make useful tools that I can use in my career as a composer. In learning Do notation the books took me through three ways of expressing the same thing before arriving at the sugary syntax that I will likely use for the next ten projects. I don't see that as building a core towards creation, but rather the elevation of a fetishy obsession with language. Children learn the most critical words before grammar - only in language studies does grammar come before vocabulary. The question is what is the core knowledge that facilitates creation? That core is a mutating form. It works from the high level downward as it needs to, not from the low level upward because it is thought that it should. There are thousands of articles on how to use raw C++ pointers. One in the know knows to use smart pointers because they facilitate creation. I constantly read authors of blog posts say things like "I wish I had learned monad transformers sooner." What is a rigorous way to prioritize learning the full scope of Haskell so that creative intuition is maximized? How can I know that Arrows will be generally more effective than Category-Extras for creating things? If data mining Hackage to find the practical reality of how Haskell is actually being used by people who are creating complete and useful things is not an effective way to learn, what approach is better? Best, Casey On Fri, Feb 1, 2013 at 10:05 AM, Rustom Mody wrote:

On Fri, Feb 1, 2013 at 9:41 PM, Casey Basichis wrote:

...

That book Mathsemantics sounds like something I should read, would you recommend it?

Well its quite a favourite of mine, if that counts as a recommendation…

...

Your point occurred to me the other day when measuring number of downloads of whole packages was mentioned as being the ideal measure.

I have more confidence in measuring the contents of the packages themselves as creating a Hackage package suggests a competency with the language and baseline of sophistication.

My thought was the best measure might be the count of functions across all packages, where an included function in any individual package would only be counted once per package.

In this sense, map and fold would still likely be towards the top, but that is as it should be.

But it seems there are many measures that would be useful, like the percentage of functions from a package that tend to get used in the same project - do people nit pick particular functions from a specific package or does the package use tend to require the use of all of its functions in every project the package is used in.

I'd love to hear some thoughts on this as I generally don't know where to begin in solving these sorts of problems and would like to know more about those methods in general.

Well… it seems to be a good idea to back off from here a bit and ask how we came here. You want to learn haskell for which you want to pinpoint the 'most' used functions. Lets leave aside the question that 'most' may be harder to specify than we may first imagine.

Instead lets make a map (functor?) from learning the programming language Haskell to learning the natural language English. So I dont know English (and yeah there are Godelian anomalies in that statement) and I gather that vocabulary is a key to mastering the language. Now Webster is a bit too fat to cram up as a whole so I decide to isolate the 5000 most used English words. Do you think my English mastery will be improved that way? Surely Webster had a bigger vocabulary than Shakespeare. Do you think Webster knew English better than Shakespeare? [You can of course replace Shakespeare to whoever happens to take your fancy]

IOW mastering the paradigm is more important than the details.

Now its important to get that the paradigm cannot be caught in any single-point sloganeering such as: "Functional programming is programming without side-effects" "Haskell is syntactically sugared lambda calculus" "The key feature of Haskell is its sexy type magic"

Nevertheless its also true that 'paradigm' consists of far fewer elements than 'the 500 most used functions.'

I have a couple of pages on my blog: http://blog.languager.org/2012/10/functional-programming-lost-booty.html gives a few of the basics that FPers should know (IMHO) before going to advanced stuff. I should mention that it was written it because Haskell is becoming increasingly hard for beginners with the focus on 'type-magic' is overshadowing the basics. [In any case after 25 years of teaching, I am finding it harder and harder to teach] If you have crossed over the basic stage it may not be much use to you :-)

There is also http://blog.languager.org/2011/02/cs-education-is-fat-and-weak-1.html and sequel which is more of a grumble about CS education than about FP/Haskell per se. Still, an undercurrent of that grumble is that much of the nonsense of CS education is because FP has not become mainstream soon enough.

-- Casey James Basichis Composer - Cartoon Network http://www.caseyjamesbasichis.com caseybasichis@gmail.com 310.387.7540

I'm not sure what you mean. I would imagine popular success for either would be circumstantial and have little to do with their actual ability and more to do with the opportunities they pursue and the cultural atmosphere at the time. For this student: http://www.youtube.com/watch?v=_bjKDJD-CLc I would have a very clear idea of the many things I would excise from the typical piano education to help her form her musical intuitions as simply and effectively as possible, with the knowledge that in time, she will find her own way to a personal style and repertoire. You are being a little cryptic. I don't see how the nuances that differentiate two experts relates. On Fri, Feb 1, 2013 at 10:31 PM, Rustom Mody wrote:

On Sat, Feb 2, 2013 at 3:38 AM, Casey Basichis wrote:

...

I just ordered Mathsemantics for a hefty $2.10.

Your article's were an enjoyable read and very informative. I'll dig more into you blog tonight.

I've read the Great Good book, Haskell school of music, and I'm working my way through Real World Haskell. I've also read countless blog articles on Haskell.

With a great deal read and understood about Haskell I have no confidence that I can make anything in it at all.

Kurt Vonnegut retyped James Joyce's work to feel a great novel under his fingers before writing his own.

Webster knew English better than Shakespeare. Shakespeare was a master of creation.

To be able to create from a small core and then extend those intuitions with knowledge over time is to me far more effective than mastering language and then attempting creation.

While not rigorous, getting hands on with high level practical libraries and working by example would have built my intuitions far faster than all of the countless reading and toy examples I've done. The problem is, for that approach, there isn't any material for a book or insightful blog post to be written. Mimetics are mundane and unnecessary to those in the know. The teachers seem to be unaware of how their own intuitions were formed.

While learning the fundamentals my mind struggles to imagine how these basic concepts play into the larger picture - how would they use foldr to build persistent? I don't have real answers to those questions but it's a constant distraction.

I am certain that sitting down with a few simple examples of how to use a library like Persistent, without any concern as to how it works, will surely take me from a useless Haskeller to being able to make useful tools that I can use in my career as a composer.

In learning Do notation the books took me through three ways of expressing the same thing before arriving at the sugary syntax that I will likely use for the next ten projects. I don't see that as building a core towards creation, but rather the elevation of a fetishy obsession with language. Children learn the most critical words before grammar - only in language studies does grammar come before vocabulary.

The question is what is the core knowledge that facilitates creation?

That core is a mutating form. It works from the high level downward as it needs to, not from the low level upward because it is thought that it should. There are thousands of articles on how to use raw C++ pointers. One in the know knows to use smart pointers because they facilitate creation.

I constantly read authors of blog posts say things like "I wish I had learned monad transformers sooner." What is a rigorous way to prioritize learning the full scope of Haskell so that creative intuition is maximized? How can I know that Arrows will be generally more effective than Category-Extras for creating things?

If data mining Hackage to find the practical reality of how Haskell is actually being used by people who are creating complete and useful things is not an effective way to learn, what approach is better?

Best, Casey

Lets say you teach the piano and two prospective students come to you. A with much passion wants to play like this http://www.youtube.com/watch?v=3L0Rncqx1yQ B with more focus than passion, has this ideal http://www.youtube.com/watch?v=Yu06WnXlPCY

Who do you think/feel would be more likely to succeed? Who would you prefer to teach?

-- Casey James Basichis Composer - Cartoon Network http://www.caseyjamesbasichis.com caseybasichis@gmail.com 310.387.7540

On 2/02/2013, at 7:05 AM, Rustom Mody wrote:

Instead lets make a map (functor?) from learning the programming language Haskell to learning the natural language English. So I dont know English (and yeah there are Godelian anomalies in that statement) and I gather that vocabulary is a key to mastering the language. Now Webster is a bit too fat to cram up as a whole so I decide to isolate the 5000 most used English words. Do you think my English mastery will be improved that way?

*Stopping* there will not let you master English, but *beginning* with a core of high frequency words is a good idea for bootstrapping. "Basic English" had 700 words. "Globish" has 1500 words. The Longman Dictionary of Contemporary English uses a controlled core of about 2200 words in all definitions.

Surely Webster had a bigger vocabulary than Shakespeare.

Many people called Webster have written. Assuming you mean the lexicographer, just because someone is able to put a word into a dictionary does not mean that it is part of their active vocabulary. (Vide Johnson's famous "Ignorance, madam, pure ignorance.") Shakespeare's active vocabulary was on the close order of 20,000 terms. (This actually seems to be a typical size for pre-literate natural language entire vocabularies.) It would be surprising if _in his other writings_ Webster's active vocabulary were noticeably larger than Shakespeare's.

IOW mastering the paradigm is more important than the details.

False dichotomy. Haskell (and English) being Haskell (and English), you _can't_ learn a significant chunk of the library (high-frequency vocabulary) without learning something about the way things are put together. You can learn the English word 'vomer' without learning anything important about English, but learn what 'although' means AND HOW IT IS USED and you have learned quite a bit. In the same way, you can't really learn 'liftM' without learning quite a lot about Haskell.

I have a couple of pages on my blog: http://blog.languager.org/2012/10/functional-programming-lost-booty.html gives a few of the basics that FPers should know (IMHO) before going to advanced stuff. I should mention that it was written it because Haskell is becoming increasingly hard for beginners with the focus on 'type-magic' is overshadowing the basics. [In any case after 25 years of teaching, I am finding it harder and harder to teach] If you have crossed over the basic stage it may not be much use to you :-)

Not just beginners, either. There _is_ a problem with the idea of trawling the top N functions from Hackage. That is that the code written for Hackage is, by and large, written to be used rather than understood by beginners. These are not necessarily the top N functions that it is useful for a beginner to use or know. It's probably better to pick one module at a time that provides a service you really intend to use and learn what you can from that. (Like learning how to read one complete story.)