F# - Resources for learning it from scratch - f#

I appreciate there are a few posts out there, asking about F# tutorials/learning resources, but so many of the questions (and answers) assume a somewhat established knowledge or experience in C# or programming generally.
While I HAVE engaged in some programming, it's been very bitty and over many years. What I'm looking for is an F# tutorial, or series of tutorials, that walks you through from the very basics (a "complete" program that prints "Hello World!"), and progresses naturally while still showing you the complete solution. Most resources I've found cut out most things and just say "this is how you'd do it in C#, and this is now F#", leaving out other elements that complete the solution to the problem.
EDIT: I found the free course on F Sharp TV (udemy course), but didn't like how it was always exploiting F# Interactive to demo the language, as opposed to building an actually complete application.

I am very new to F#. I just started picking it up this month and I have really enjoyed it so far!
I can really relate to your question because every book or tutorial I've found assumed a lot more knowledge than I had. I would open them up start reading and then 3...2...1...and I was completely lost.
I'm sure once I am better at the language the references that are usually listed will be obviously superior to what I'm about to recommend.
One book I've enjoyed is "Functional Programming Using F#". It starts from the very, very basics and provides information about the small things in F# that I otherwise would have missed. The best part are the exercises at the end of the chapters, because someone went through all of them and posted answers here: [1]. So you can struggle through the exercises and then get an idea of how someone else approached the problem! The main drawback of this book is that the examples can be math heavy at times.
The second book I've used is called "Friendly F#". I really have never seen it linked or talked about, but I have thoroughly enjoyed it. I have found the approach the author takes to be rather novel. Instead of showing me how to implement the Fibonacci sequence in F# for the bajillionth time the author starts with projects! Real projects where you can actually visualize things! For example, in the first chapter you create an F# script where you visualize a ball bouncing in a box acted on by gravity! I know real coders are probably more worried about the esoteric features of the language but as someone starting out it was super motivating to actually be able to visualize something and more importantly to have something to show to my wife so she won't think I'm just wasting hours doing nothing. 😁
The last thing I'll recommend is Excercism. It's a great website where the tutors give great feedback. The only drawback is that you need to have somewhat of an idea of what the language can do. For me, I wasted countless hours trying to solve one of the problems only to realize that there is something called Seq.zip which would have solved the problem instantly. So, I recommend sitting down with a problem thinking hard on it for an hour and then googling "fsharp excercism solutions insert problem name here". Luckily, you can navigate directly to the solutions page and go through hundreds of solutions that other folks came up with. That's how I learned forever what Seq.zip is.
EDIT:
I also wanted to add this video [2]. It's not going to teach you all you need to know about F# in one video. However, it will give you a great overview of the language so while you are learning it in more depth you have an idea of what the language is capable of.
I hope this helps!!
[1] - https://github.com/TorbenRahbekKoch/Functional-Programming-Using-FSharp
[2] - https://www.youtube.com/watch?v=c7eNDJN758U

As mentioned in the comments, some might think this answer can be seen as opinion motivated. I feel that those resources could be a good entry point to learning more about the language.
Reference: sachabarbs.wordpress.com/1406-2
Reference en.wikibooks.org/wiki/F_Sharp_Programming
Bonus: Getting started with F# in the cloud with Azure, take a peek at this awesome reference!
Reference: Getting started with F# with Azure Notebooks

I would recommend first fsharpforfunandprofit.com - clearly a big starting point. You have the complete. This is a great section to "thibk functionally". https://fsharpforfunandprofit.com/series/thinking-functionally.html
When you get used to the language (a little bit), I would recommend "Stylish F#" . It is a very recent well written book on good practices for beginners (but who can write a bit of F#). Really liked it.

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Path to Become a Better F# Programmer [closed]

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I would like to hear from you folks that have achieved a high-level of proficiency in F# (and also in functional programming in general too) what should be my steps from now on to become a better/professional F# programmer?
I already know much of the F# syntax and have some years of experience with C++. My goal is, as an engineer and mathematician, to design better scientific libraries (linear algebra packages, partial differential solvers, etc.).
what should be my steps from now on to
become a better/professional F#
programmer?
Keep coding everyday :)
I jumped on the F# train in Sept '07, before that I had a boatload of C# experience. It took about 3 months or so for me to stop writing code as C# with a little funnier syntax and start picking up on the right coding style :)
Tips and things that helped me:
I found that F# makes it really hard to write non-idiomatic code, really easy to write good, clean code. If you find yourself fighting the compiler, 9 times out of 10 your doing something wrong. Go back to the drawing board and try again.
The entire concept of immutability was a mystery at first, but implementing all of the data structures from Okasaki's Purely Functional Data Structures was hugely helpful.
During some slow days at work, between '08 and '09, I wrote a wikibook. I haven't looked at it in a while, but I'm sure its really bad --- but, the experience of explaining the language to others was a good jumpstart for someone like me who normally wouldn't have enough motivation to start a pet project in F# :)
Map, Fold, and Filter are your friends. Try to express algorithms in these functions rather than implementing a loop with recursion.
Non-tail recursive functions are almost always easier to read and write. See here.
Project Euler. Lots of people recommend it, I didn't find it particularly helpful at all. You might get more use from it than me if your a mathematician, however.
<3 unions! Use them!
Falling back on mutable state -- big no-no. At least for beginners. The worst beginner code is full of mutables and ref variables. Immutability is an alien concept at first, so I recommend writing fully stateless programs for a while.
Still, the best advice is just keep coding everyday.
Hope that helps!
-- Juliet
Like any other language now that you know the syntax and the basics it's time to write code and more code.
Make sure you have the core concepts of functional programming down.
Work on a large project so you also get familiar with the large and not just the small.
Write a few immutable data structures.
Work on a large project without using inheritance.
If your familiar with design patterns implement some of them in a purely functional way and notice how some of them disappear.
F# is about mixing functional and OOP styles. Once you've done a fare amount of abstraction without inheritance bring it back and start mixing the styles together. Find a balance.
Since your goal as an engineer and mathematician is to design better scientific libraries may I suggest as a learning exercise working on a video game style simulation. Something that involves physics and math but also requires control of state.
I can only agree that trying to explain functional programming to others is a great way to learn it. I spent a lot of time about thinking the structure of my F# book and I think it really helped me to understand how functional concepts relate. Even giving a talk on F# in your company or to your friends should have a similar effect.
When I started learning F#, I started working on the F# WebTools project. I think this was quite useful, because many components of the project were perfect for functional programming, so I learned many functional tricks (because they were the best way to solve the problem). The project processed source code tree of F# and translated it to JavaScript, so I was using a lots of recursive functions and discriminated unions.
The area you're working in is quite different than my, so I cannot give you any specific advice, but it is a good idea to write programs in a clear functional way - even if you think that it would look nicer if you wrote it in the C++ style. When you write it, you'll probably find some way to simplify your code.
So, I think that the tips I could give are:
Try to explain F# to others - this helps you to organize ideas in your mind
Pick good problems to start with - e.g. algorithmic problems, processing tree structures, etc.
Write as much F# as you can and don't be afraid to start with a solution that does not look perfect to you - I rewrote my first program so many times!
you very probably don't want to hear from me as I have not achieved a high level of proficiency with F#, but I have set myself the goal of getting there (much like your self).
I thought I might suggest what has turned out to be my biggest learning tool: Stubbornness.
I set my self a large-ish project (a game, just as gradbot suggests). I then decided to code using as much immutable data as possible regardless of the performance costs.
Then if I couldn't find a way to use immutable data I'd come here and ask for help.
The hoops this stubborn approach forced me to jump through has been a brilliant learning exercise, as (just as Juliet mentions) F# allows you to write really ugly C# if you let your self get lax.
Right now I have tile based 2D world and a little man who can find his way to the treasure and back home again using A* path-finding ... The only thing I mutate is the title of the window it's displayed in.
I only got serious about learning F# towards the end of July (I'd dabbled before then) and this project has taught me a huge amount, along with the help of the guys here at StackOverflow.
The other answers do a good job of suggesting ways to practice your F# writing skills, which is obviously very important. However, something which doesn't seem to have been emphasized much is reading F# code, which is just as important in my opinion. There are a lot of people doing cool stuff with F#, and one of the best ways to learn about the different corners of the language is to read about what they're doing. This will help you pick up idiomatic style and will also expose you to more design patterns, language features, and functional programming techniques than you would be likely to encounter if you were just solving a problem using F# on your own.
The F# blogs syndicated on Planet F# are a good place to start, but there are also several excellent books and presentations on the language.
This only answers part of your question, but as you talk about wanting to create libraries in F#, the F# component design guidelines just came out:
http://research.microsoft.com/en-us/um/cambridge/projects/fsharp/manual/fsharp-component-design-guidelines.pdf
If you are interested in scientific libraries I suggest you to take a look at Jon Harrop's F# for Scientists.
Also to catter for your mathematician side I suggest you to read Doets-Van Eijck The Haskell Road to Logic, Maths and Programming, although written in Haskell, you will certainly be able to follow most of the text, and re-implementing the samples in F# could be a nice exercise.

What are good "real" programming examples for a beginning programmer? [closed]

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I've been browsing Bjarne Stroustrup's new introductory programming book, Programming: Principles and Practice Using C++. It's meant for first-year university computer science and engineering students.
Early on in the book he works through an interesting extended example of creating a desktop calculator where he ends up implementing an arithmetic expression evaluator (that takes bracketed expressions and operator precedence into account) in a series of co-recursive functions based on a grammar.
This is a very interesting example, although arguably on the complex side for a lot of beginners.
I wonder what others thing of this particular example: would learning programming by seeing how to implement an expression parser excite and motivate you, or would it discourage you because of all the details and complexity?
Are there other good "real" programming examples for beginners?
When I was first learning to program, the best example I ever worked with was building a text adventure game from scratch. The basics just required knowing how to display text on the screen, receive input from the keyboard, and rudimentary flow control. But since text adventures always have room to add more features/puzzles/whatever, they can be easily adapted to explore aspects of whichever language you're learning.
Of course, not everyone finds games more interesting than calculators. It really depends on the programmer.
First, let me say that cognitive psychologists have proven in numerous studies that the most important factor in learning is desire to know.
If you want to learn about programming, you need to find a domain that stokes your desire to understand. Find a challenge that can be solved with programming.
I agree with the other folks when they suggest something that you are interested in. And games seem to be a common thread. As I reflect on my experience learning to program (too many years ago), math problems and a simple game was involved.
However, I don't think I really understood the power of software until I created a useful small program that helped a business person solve a real problem. There was a tremendous amount of motivation for me because I had a "client". I wasn't getting paid, but the client needed this program. There was sincere pain (gotta get my job done quicker) related to this situation.
So my advice is to talk to people you know and ask what small annoyance or computer-related obstacle to they have. Then try to fix it. It may be a simple web widget that reduces repetitive, manual tasks for an office worker.
One of my best early works was helping a little printing shop (no software, circa 1985) that struggled with estimating jobs to produce proposals that weren't money-losers. I asked alot of questions of the sales lady and of the operations manager. There was obviously an intersection of a common pain point with a really easy calculation that I could automate. It took me a couple of days to learn Lotus 1-2-3 (spreadsheet for you young-uns) enough to write a few macros. I was motivated. I had passion. I saw where I could make a difference. And that, more than anything else, drove me to learn some simple programming.
Having real people, real problems, and really simple solutions could be the inspiration you need as a beginning programmer. Don't try to write an accounting system. Just take one discreet piece of someone's frustration away. You can build on that success.
So, I wouldn't focus on the technique (yet). Don't worry about, "Am I doing this the most efficient way?" The main objective for a beginner is to have success, no matter how small, and build confidence.
BTW, that Lotus 1-2-3 set of macros grew into a full job tracking system. Very archaic, limited features, but made that little print shop much more profitable.
Create your motivation, fuel your desire, and develop your passion for programming like an artist unveils the masterpiece in a blob of clay. And be persistent. Don't give up when challenged with a roadblock. We all get stumped sometimes. Those are some of the best learning moments because humans learn more from failure than success.
Good luck.
I think making tiny games like text version of Tetris will be a good way of getting into pragramming world.
Board games are fun to design and code since they come in many shapes and difficulties
from tic-tac-toe to checkers to monopoly, its reinventing the wheel for educational purposes!
the best advice i can think of is to pick something from a field of interest you have because coding for the sake of coding might dim your resolve
Start small. Do examples that interest you. Stretch yourself just a little every time. Get comfortable with each step, to the point that you have confidence that you know what you're doing, and then try something a little harder the next time.
I think that any example program would help you learn a new language, but a beginner should try to work with something that is easy to understand in the real world, such as a mortgage calculator or something along those lines.
I think the answer is that it would depend on the person who is learning how to program.
One nice thing about something like an arithmetic expression evaluator is that it is a project that can start very small (make it work with just the format "X SYMBOL Y" where X and Y are single-digit numbers and SYMBOL must be a plus sign) and then you are slowly expanding the functionality to the point of a complicated system.
However, it might not be a great starter project for someone who doesn't really understand the concept of computers (hard disk, memory, etc.)
Try to think of something that you do on a computer that is repetitive, and could be easily automated. Then try to come up with how to make a program that automates that task for you. It can be anything, whether it's popping up a reminder every 15 minutes to stretch your legs or cleans up your temp directory on a regular basis.
The problem with this task is that it's conplex and not real life related. I don't need another calculator.
But once I had a CD with scratched surface near its center and lots of valuable JPEG files inside. I dumped the data from the unscratched part of the disk but all the filesystem was surely lost. So I wrote a program which analysed the dump and separated it into files. It was not very simple but was a nice and exciting file IO programming exercise.
Examples can be more complex than something you try to write yourself. It's easier to follow someone else doing something than it is to do it yourself. A real-world example like this calculator may be a fine way to introduce someone to a language. For instance, Practical Common Lisp starts with an example of an in-memory database (for CDs I think) and uses that as the springboard to explore parts of the language.
I prefer seeing a real example built up over time than just a lot of simple "Hello World" programs.
I've always found that implementing a game of some sort is sufficient incentive to learn various features of a language. Card games, especially, because they generally have simple rule sets to implement, but are sufficiently complex from an abstract point of view.
I would agree, though, with everyone else: find examples of things that interest you. Not everyone is a game fan, but something like a mortgage calculator would be far more interesting.

Pair Programming for a job interview [closed]

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Our company has been thinking about scrapping our interview procedures and bringing each candidate in for a 4-5 hours sit-down with some of the programmers and just do some pair programming.
I like the idea in theory but I am not sure how you can really make it fair for each candidate. How would you rate them? Wouldn't their input really depend on what each programmer was working on that day?
Any thoughts on whether this is a good idea/bad idea or how to make it work is what I am kind of looking for here.
Cheers!
EDIT:
RESULT - AS requested
We are going to conduct the first steps of the interview the same as before. Phone followed by face to face. Instead of bringing them back for a third and final grilling, we are going to bring 3 developers back to sit with all 7 members of the team. We have decided to let the team decide who is then hired.
We have come to this conclusion for a couple of reasons. We believe this will empower the developers by giving them a choice who they are working. The second reason is group dynamic. We think it is really important to have a good group dynamic and it is hard to tell until after you hire a person if they will fit in or not.
So the end result is we are going to go ahead with the pair programming sessions but in a completely different way and for a completely different way than was originally intended.
Any thoughts or criticism of this approach is more than welcome!!
(this edit is posted as an answer below so feel free to downvote if you feel this is not the best approach)
Unless you use pair programming extensively in your real-world development, I'd be very hesitant to use this. I've met any number of high-quality professional developers who have mentioned a strong aversion to pair programming and whose skill would not be well-judged in such a process.
I hope you have a bunch of steps ahead of this one. For this to work you need an excellent resume and phone screen. You don't want to spend oodles of time on candidates that you shouldn't be talking to in the first place.
So you suggest an initial interview
and possibly have the second interview
as the pair programming session? – Ted
Smith (1 min ago)
Yeah. You might even think of having a simple coding interview happen over the web using something like CoPilot.
The easiest way is to give each person the same programmer to work with and the exact same piece of code.
The problem you're going to run into, is that hiring isn't like programming. There isn't a step by step process to lead to the right answer as to who to hire. (you can have multiple steps to make the decision easier). You have to evaluate each one on their strengths etc. and essentially make an educated guess as to which is the best one to hire. Sometimes you guess wrong.
The other thing about pair programming you're going to have to watch out for is the amount of time necessary to have each candidate at that stage go through that kind of a test. If I were looking for a job, I would be hesitant to go an interview at a company that would ask me to do that. Why? Because that is a lot of time, and if I am interviewing at multiple places, I could spend literally days just going to interviews for jobs I may not even get or want. Someplaces like Google or MS would be an exception, but most places are not like those two. (Not to mention the fact that if they are working on real code, you are essentially asking them to do someone's job for free).
As a personal anecdote, I got smacked around in an interview because of a technique like this. I had gone far in their interview process; passed the resume checks, the code submission and this was the face to face portion of the interview.
I was fresh out of university and had never pair programmed before nor done TDD. They sat me down to do a deck of card exercise and it flopped. Badly! I didn't understand why the interviewer was writing tests that seemed so dumb* (IE "return null;") and they didn't explain why and of course being foreign to TDD I didn't know what questions to ask. The end result was that it looked like I couldn't program my way out of a paper bag.
If you're going to do this type of exercise you need to cater to the interviewee because they're going to be in different spots with their aptitude. This means that you'll get different assessments that may not be based on actual talent and are thus going to be heavily biased.
**Now that I understand TDD, I do understand tests like this and how it's supposed to work, but man did that ever seem stupid at the time!*
I just had an interview with a San Francisco based company that prides itself on Agile methods/etc. I was to interview the CEO himself. I have about 20 years of experience in the industry, but have never pair programmed or developed using TDD approach. I was told it would be a "programming interview" but had not idea what to expect, and before we started the guy said that he thought that I may agree that all interviews should be done this way. (which in retrospect was nothing more than an arrogant statement).
Anyway, at the interview the exercise was to develop a class using TDD. It took me a second to adjust my thinking on the entire process, again since I had never pair programmed or done TDD. While I stumbled here and there I did ok in the end. but his reply was the I did not exhibit the aggressive back-and-forth nature that they require for their pair programming environment. Now, that could also have been an underhanded way of saying that "I didn't think you did great" kind of message.
Luckily I didn't need the job and to be honest the experience made me realize that I'd rather find a different career than having to be a software engineer that HAS to work in pairs, day in day out, when it came to developing code. Odd thing is that on occasion I have worked with another person on code simultaneously, so anything is possible.
In end I guess it was a good outcome since they didn't think I was a good fit and I didn't care for their working methods. But we would have came to the same conclusion had I talked a for a few minutes more about myself and had he given me a little more info on how they go about their work. Which is to say that there are other ways of finding a good fit candidate than putting them through the stress of pair programming with a complete stranger; bogus way to gauge competency imo.
One particular company uses a technique called extreme interviewing. For the extreme interview they will bring in say 30 developers and group them into 15 pairs. They will explain that they are looking for people who work well with others. That they will make a hiring decision based solely on their ability to work with others.
They will provide a problem for the pairs to solve. They will emphasis that they are not interested in the solution just each programmers ability to work with others. For each pair they will provide an observer of the pair. During the exercise (about 2 to 4 hours in duration), the observer will takes notes about a person ability to pair ... not the solution.
They are amazed how many programmers focus on solving the problem instead of collaborating. Of the 15 pairs, they will identify about 4 to 6 developers for a second interview. Those developers will be asked to come back and spend a week with the team (they get paid). After a week, they decide who to keep. Generally about half of them (2 to 3 developers).
When they are done, they have developers that are able to collaborate and after a week working with various pairs, the team has a strong indication who can effectively develop software. The process is both innovative and effective. They have had a high success rate with those they have hired.
I just had a pair programming interview a few days ago and to be honest, I don't really like it. I was notified of this a day just before the interview and then the interviewer told me that pair programming is what eventually I am going to do anyway in work. I went into the office and was paired up with someone who is a very senior software engineer. The company is in San Francisco and they are a well renowned company for pair programming, everyone pair programs in the office. At first it seemed to be fine, he explained about all the tools they used, their own unit testing framework that they build, and a bit of the project. He then basically wrote a bunch of unit tests and wanted me to work on the implementation to make it pass. Just as an FYI, the code base that already exists is huge, I would say 10k lines, it's not like a super complex project, but it is complex for someone to just step in and then write code without prior understanding of the class hierarchy etc. I find it really hard to believe that he expects someone to jump right away in a 10k line of source code that already exists. It just doesn't match for a pair programming interview, a smaller code base would help. I struggled a bit from navigating through the classes and going back and forth because I can't remember class names as I was overwhelmed by the amount of classes/code that already exists. To be honest, this really made me do horrible in the interview process. In the end I didn't feel really good about it. I haven't done pair programming before, mostly is just during assignments in my college year.
To me the power of pair programming can be harnessed if you're already proficient/comfortable with your pair, but is not really suitable for interview. Sometimes I would like to ask questions to my pair, but then I thought if I ask too much questions, then they would assume I were stupid and can't perform. If this was already on a real job, I wouldn't hesitate to ask, but in an interview it's hard.. you want to ask because your pair should help you out when you're stuck, but at the same time it's an interview, so you can't really ask much.
That is just my experience that I have from pair programming interview, my suggestion if you really want to do this:
be sure that you don't give the candidate to work with a large code base, work with a
smaller one and therefore he/she can show his/her skills to the max
be up front with the candidate before pair programming interview, can you ask questions
when you're stuck, should you be able to do this and that, what can't you do
be as detailed as possible
In the end, I wouldn't suggest it. It's hard to measure a candidate's performance in pair programming, and it might be biased as well.
I like this idea. However I think it might be difficult to do since it would require the candidate to have some knowledge of the project you would pair on with him. Also, 4 to 5 hours seems a bit long. What if you immediately see that it is not going to work out, are you going to sit through the whole session with the candidate?
Good question though. Stuff to think about.
Why not? Also, it's not like interviews are always (or ever) fair. You should evaluate the end results of the new approach against the traditional interview-based approach.
Also, a mini interview before the pair programming session might be good to keep from wasting the programmers' time with people who would be a bad fit.
From my limited experience, my feelings are mixed. I like the idea of pairing as part of an interview, esp. if the company uses pairing often, because it gives both a better feel for the fit. As a candidate, I've often gone through interviews where I sat in a room answering questions for a few hours, but afterward didn't have a good feel for what it would really be like to work in their environment. Pairing may be more beneficial than a random coding exercise, unless the interviewer is skilled at working someone through those. And I like being able to discuss technical stuff from both sides. And as a candidate, I'd rather interact with someone than just answer questions or solve code problems on my own.
But... as others have noted, the time needed can be an issue. I've gone through a couple days of pairing interviews and found some periods good, while others felt like a few hours were wasted: one because the developer wasn't working on something that lent itself to pairing (esp. given my background), the other because an env issue prevented much useful work for a while. If the job doesn't work out, it can be frustrating to have taken a day or two off work for this.
One place trying this approach wasn't sure if they should have someone outside the company working on a customer's project. They also worried that explaining the domain and work being done would take too long, though without that the candidate may not be able to contribute much. So they chose an open source project the employee was working on.
This seems to be a key point: there needs to be a well chosen task that the candidate can understand quickly and be able to contribute to. The latter part will depend somewhat on the candidate's skills. Also key would be the employee's ability to evaluate someone with this approach. Not everyone is great at normal interviewing, and that's probably more true of a pairing interview.
Also, if a company doesn't do much pairing then this kind of interview may not be as useful. There does seem benefit in seeing someone code (as Joel Spolsky notes), and this could be a good way to do that. But if pairing is not a typical part of the job, then perhaps a full pairing session isn't appropriate. Maybe a modified version.
I'd be curious what companies who have taken this approach think of the results. Reading some of the other answers to this question shows that it doesn't always seem ideal from the candidate's view.
To keep it fair, you'd have to make every participating staff member have a prepared problem to evaluate the candidate on. Preferably something taken form the real world in their company experience, but something that has already been resolved. This is a good chance to evaluate the knowledge on a problem and evaluate not just programming skills.
I hate it when too specific questions are answered. I had an interview once where a programmer was testing my knowledge of the STL which I used extensively and was trying to get me to answer that a custom allocator was needed. I had heard of them but never used them (esp in windows) and was made to feel dumb. IOW, avoid being judgmental.
So my point is, ask practical questions that aren't so much about testing programming knowledge as you can evaluate more qualitative personality and problem-solving approaches if you use the "pair programming" idea.
Good question!
Honestly, that sounds like a great idea, though Jason Punyon is certainly right that you should do a lot of weeding before you waste significant amounts of your developers' time on culls. You get a glimpse at an important metric out of it that's otherwise nearly unobtainable in interviewing: what someone's like to work with.
I don't think there's really any need to be concerned about it being "fair" based on the subject matter or trying to present consistent situations to different candidates, if you maintain the right evaluatory attitude -- that it isn't about whether they "got the right answer" or jumped through the right set of hoops, but what sort of effort, problem-solving, communication aptitude and flexibility they showed. You'd lose most of the benefit of the exercise by turning it into an artificial test, not to mention changing it from something that your developers can get some benefit from (or at least still get some work done during) to a massive waste of their time.
Joel Spolsky has an excellent Guerrilla Guide to Interviewing which talks about, amongst other things, programming tasks.
Trivia: Joel Spolsky is a co-founder of stackoverflow.com

How to approach learning a new SDK/API/library?

Let's say that you have to implement some functionality that is not trivial (it will take at least 1 work week). You have a SDK/API/library that contains (numerous) code samples demonstrating the usage of the part of the SDK for implementing that functionality.
How do you approach learning all the samples, extract the necessary information, techniques, etc. in order to use them to implement the 'real thing'. The key questions are:
Do you use some tool for diagramming of the control flow, the interactions between the functions from the SDK, and the sample itself? Which kind of diagrams do you find useful? (I was thinking that the UML sequence diagram can be quite useful together with the debugger in this case).
How do you keep the relevant and often interrelated information about SDK/API function calls, the general structure and calls order in the sample programs that have to be used as a reference - mind maps, some plain text notes, added comments in the samples code, some refactoring of the sample code to suit your personal coding style in order to make the learning easier?
Personally I use the prototyping approach. Keep development to manageable iterations. In the beginning, those iterations are really small. As part of this, don't be afraid to throw code away and start again (everytime I say that somewhere a project manager has a heart attack).
If your particular task can't easily or reasonably be divided into really small starting tasks then start with some substitute until you get going.
You want to keep it as simple as you can (the proverbial "Hello world") just to familiarize yourself with building, deploying, debugging, what error messages look like, the simple things that can and do go wrong in the beginning, etc.
I don't go as far as using a diagramming tool sorry (I barely see the point in that for my job).
As soon as you start trying things you'll get the hang of it, even if in the beginning you have no idea of what's going on and why what you're doing works (or doesn't).
I usually compile and modify the examples, making them fit something that I need to do myself. I tend to do this while using and annotating the corresponding documents. Being a bit old school, the tool I usually use for diagramming is a pencil, or for the really complex stuff two or more colored pens.
I am by no means a seasoned programmer. In fact, I am learning C++ and I've been studying the language primarily from books. When I try to stray from the books (which happens a lot because I want to start contributing to programs like LibreOffice), for example, I find myself being lost. Furthermore, when I'm using functionality of the library, my implementations are wrong because I don't really understand how the library was created and/or why things need to be done that way. When I look at sample source code, I see how something is done, but I don't understand why it's done that way which leads to poor design of my programs. And as a result, I'm constantly guessing at how to do something and dealing with errors as I encounter them. Very unproductive and frustrating.
Going back to my book comment, two books which I have ready from cover to cover more than once are Ivor Horton's Beginning Visual C++ 2010 and Starting Out with C++: Early Objects (7th Edition). What I really loved about Ivor Horton's book is that it contained thorough explanation of why something needs to be done a certain way. For example, before any Windows programming began, lots of explanation about how Windows works was given first. Understanding how and why things work a certain way really helps in how I develop software.
So to contribute my two pennies towards answering your question. I think the best approach is to pick up well written books and sit down and begin learning about that library, API, SDK, whatever in a structured approach that offers real-world examples along with explanations as to how and why things are implemented as they are.
I don't know if I totally missed your question, but I don't think I did.
Cheers!
This was my first post on this site. Don't rip me too hard. (:

Did you feel learning to program with turtle graphics was useful? [closed]

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I'm preparing to teach someone to program. When I learned the course material, I used turtle graphics for the first few exercises. In reading introductory textbooks, I have not found one that uses the technique. Did others find this approach helpful? If not, what is a better way to learn to program?
I think it depends on age of the target group.
If they are children (I would say up to 12-14 years), doing any easy graphics is a good way to motivate them; on the other hand, don't expect them to learn much about real programming or algorithms.
If they are teens (14-18), it's perhaps still good to use some algorithms that give pretty results (for example 3D or fractals), but since they are older and capable of more abstract thinking, I don't think 2D turtle graphics is interesting enough.
If they are older, doing any graphics is a distraction. At that age, they should have enough inner motivation to learn without anything fancy.
To sum up, I think that fancy graphics serves more motivational role (that you see what you did fast, and it's easy to show others what can you do with a computer) than learning role (that it would make learning real programming easier).
In the late 80s, before I was programming in C, I was programming in Applesoft BASIC and Logo. As a child I thought the turtle was great because it make programming simple. If I decide to teach my children Logo I will probably start here to get an actively developed Logo interpreter.
The key thing about LOGO is user-defined functions. It is very good at conveying that, as long as you emphasize it. Show interactively how to draw a square, then make a new word called square. Then show how you can draw patterns using square. Then make those patterns into words, and so on.
You could do worse in teaching programming than using a tool like Scratch. It's a drag and drop programming interface and can be used to teach basic concepts of programming with some fun visual results (as can be seen from the gallery on their website).
Rob
Logo gave me a very clear picture (no pun intended) on how recursive functions would work, and since I was doing assembly programming at the time, the need to return to the previous state when returning to a method became very clear with Logo.
Recursive implementations of things where also very easy to see the effect of.
I wrote script/code in a c-like dialect for a game called Doom2 before I knew what programming was, so when it came to seriously learning about concepts such as pointers, inheritance and polymorphism I found the basics a breeze because I could construct a mental model to not only help me understand, but also appreciate how cool things like pointers and arrays are.
A friend of mine is a good programming student, but he gets frustrated when he can't visualize an algorithm working, when I was starting to help other students I found they had the same problem, if they can't see something working it's harder to appreciate as a fledgling programmer, the same friend eloquently suggested I "Show 'em some crazy pimp shit and then show them how it's done". He's right, even if someone really wants to learn something they'll be able to draw on more mental energy if they think what they're learning lets them do awesome things.
My best bit of advice is this: AT THE START SPEND AS LITTLE TIME PROGRAMMING TO THE CONSOLE AS POSSIBLE
It makes you feel constrained and your efforts appear futile, only after you appreciate it as a front end should it be used for learning to program. I wouldn't use logo myself because I don't think it can teach concepts such as the aforementioned polymorphism or inheritance nearly as well as other methods, I know a friend of mine is teaching a teenager how to program using XNA in a wrapper, I think anything that can let you blit an image to the screen is fine. That way you can see why you'd want an abstract base class called EnemyEntity with behavior that's inherited by zombie and dog etc. It's not that the concepts are hard to understand, it's just that at first they're hard to appreciate.
I could go on but I think that puts across what I've learned by teaching others. I think using graphics in teaching programming allows students to gain the ability to build mental models of intangible concepts faster than any other.
XNA If you want to teach C# that's an amazing graphics library, just write a wrapper sprite class to hide as much complexity when first starting out and teaching concepts.
SDL A lower level library if you're going to start with c++
During one of my first-year computer science papers we used Java to create fractal patterns via a turtle object.
It was pretty fun to see visually whether or not we had correctly implemented the algorithm required to produce a certain pattern. However, so answer the main question, I wouldn't say that programming via a turtle is useful. I'd say the best way to teach someone to program is to get them to build their own app to do whatever they want it to do. This gives them creative control, plus if they get stuck they can learn how to resolve a problem.
I strongly suggest to start with a interpreted language like Logo (not compiled) because of the quality of the error messages. Reading error messages is very important in this process. Also, at the easy level, Logo allows you to run your instructions one by one in direct mode and carry them to your procedures when you get the expected results.
# Alex: MicroWorlds is a commercial version of Logo and it does exist in English, Spanish, Portuguese, Italian, Russian, etc. it's a big plus if you are not a native English-speaking person.
LOGO is not only Turtle-Graphics.
There are also other interesting concepts in it which come from LISP.
'Turtle' is just icing on the cake and the "imperative" side of Logo.
:)
I learned to program in BASIC by writing simple programs drawing faces (I mean circles and squares) on the screen. Somehow the whole turtle programming was never my thing, although a few of my friends learned that way. Later on I moved to Pascal, then to Delphi, Java and C++/C#.
In my opinion the trick is to "wow" your student and impress/empower with potential things that you can accomplish by writing your own programs. I would actually demonstrate some GUI programming or game programming. It's much easier to learn the basics by keeping the end goal in mind.
Recently I came across SmallBasic - a cool programming environment for kids designed to teach concepts. I would give that a try. It comes with a pretty complete paper describing how to use it.
When I got my first computer (VIC-20) and started programming it was very hard to explain to my parents what I was doing.
My mother tok a course in computing preparing for a project of computerizing the library she worked in. They had a couple of classes introducing them to programming. After learning LOGO she came home and said that she suddenly understood what I was into.
So LOGO with turtle graphics brought us closer together!
I did a "computing for kids" course in the late eighties, and there was an extensive section on turtle graphics using logo. In all honesty I was bored to tears, and learned virtually nothing from it.
I think "programming the turtle" might work better for someone who is artistically inclined, or hugely into geometry, but by and large, there are far more interesting problems to attack, even for kids.
Ah, the memories of good old Logo. I think I got more of a geometry lesson than a programming lesson out of it, e.g. figuring out how much to turn at various points to produce a particular shape, design or pattern. It may work if you plan on mixing geometry with the programming, but if the person doesn't have the basics of geometry, e.g. what is a square and how is it different from other 4-sided shapes, what is a triangle, etc.
I used logo and turtle at school too, a great introduction.
It looks like our kids will be getting a slightly updated interface with Microsoft Kodu. It looks very impressive. It's an icon based programming language made for creating games that runs on X-Box Live.
I'm currently learning python and using a little bit of turtle. In labs we haven't used it, but our homework does. It's nice to know it exists, and it's a good way to get certain commands and syntax in. Overall I don't feel it was completely necessary though.
When I was young, I found it very interesting. It was one of the first programming languages that I've learned, even though I've used it for about two days. It started my interest in programming.
Nowadays, I think the syntax is a bit unclear because most statements are abbreviations. Nowadays, computers are far more powerful thus the language could profit from clearer statement. Another factor is the native language of the person who is learning to use it. If English is not your native language then Logo becomes a bit more complex to understand. So if you're teaching Logo to children, make sure they're familiar with English terms first. (Quite easy if you're a native English-speaking person. More complex if you're originally Dutch, German, French, Portuguese. Even more complex if you're Russian or Chinese because you'd have to adjust to a different character set too.)
I have just begun teaching my 7-year-old how to program using Logo, and he is having a load of fun with it. The commands are easy enough for his limited reading ability and he just loves drawing cool pictures using the turtle graphics. I was amazed at how well he retained what he had learned using it, so I feel it was a good choice for his age.
For older kids (or adults) other languages might have more advantages as a beginner language though
Personal experience, YMMV...
My first encounter with a computer was turtle graphics in my early teens. I loved and was immediately hooked. (Perhaps because for the first time someone [something] did exactly what I told it to do?)
The visual and instant feedback made me want to do more and more. I really wanted to figure out how to replicate the pictures I saw in the book I was using. Without me even classifying it as "work", it slowly built up my early programming skills and my confidence I could learn on my own.
I credit it with sending me in the path I'm in today, a happy software developer who can't believe I get paid to do this work (I know, I know - all corporate snickering aside, I like my work).
As I said, YMMV.

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