Comment by jgable | Hacker News Reader

Comment by jgable | Hacker News Reader

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I am. I know python quite well, but I did not understand functional programming before I read this article. Oh sure, I'd looked it up on wikipedia, and read a few blog posts, and perused a Haskell tutorial, but none of that made it click. Too many new concepts at once. Using python as the instructive language is great simply because many people know python, and for those who don't, the syntax is easy to follow.

This article was perfect for me. The "guide rope" paragraph instantly clarified and put into context all the other disjoint pieces of information that I had picked up.

I can now see how to apply these concepts in almost any language. Right away, I can see how to refactor my side-effect-riddled C++ to make it more suitable for unit tests.

I came across this piece after following a previous story on HN, and was very tempted to post it at the time, because it really helped me.

It really is an excellent introduction to FP, but:

> I know python quite well, but I did not understand functional programming before I read this article

Sounds like someone who would have benefitted from practical uses of FP in python, such as comprehensions.

...It's a really neat article, but I think it would have been considerably improved with asides for "And here's an even cleaner way to write this, if you're using python"

I do know list comprehensions, and I use them all the time (not trying to be defensive here, just providing context). I understand that they are just a different syntax for mapping -- applying a function to members of a list to produce a new list. However, while list comprehensions are clean and pythonic syntax, I think the "map" syntax more clearly illustrates the concept that the author is trying to teach.

Your suggestion for asides is certainly valid, and I agree would make it more useful for budding pythonistas. I just think that her focus was to introduce functional concepts, and python was simply an easy language to make the concepts concrete. I think that it's stretching the scope of the article, and therefore watering down its message, to put any additional focus on specific features of the python language.

I guess this is an example of my earlier point: I knew about map and reduce, and understood their power. However, it had not clicked for me before reading this article that they feature so prominently in functional programming because they work with functions that have no side effects.

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