Days go by like seconds… I owe my blog 3 posts already - I created the drafts and I am still not able to go back to them, proofread them and make them descent for posting…
There was a learning this week… It is nice to mix different stuff to learn together BUT NOT IN ONE DAY!This is the major reason I didn’t finish the previous posts - I ended up so confused at the end of the day and thought I would make it better the next day. Weeeeeell, no!
I am not gonna make a “finish by then-or-that-time your post” rule, I am just gonna make sure that everyday I am able to word my learning, without thinking of how people would judge it. Just kidding, of course I care! During the first days of the apprenticeship, I thought it was just me and my baby blog #NOT So, of course I care if people like it/ find it useful /enjoy it /have fun with it… To be honest a greek blog is a secret dream that I have always had - the only thing (or excuse) that stops me is time. But enough with the Friday confessions, let’s spice this day up with some curry-ing (Ha-Ha).
Currying
This gif would be enough if this were just a tweet, but as this is not the case let’s go:
Why currying? It was my first question, but the answer’s not that exciting - it is named after Haskell Brooks Curry. Yes, the Haskell language, where a lot of currying is happening, is named after him as well.
How come you learned today currying? Today I focused on FP concepts. I went back to Ordesky’s course, speed it up and it FINALLY seemed like a normal course ( THANK YOU SEBASTIAN! ). It was left at the 2nd chapter and “High Order Functions”. Currying was only a 14min video, so who could have imagined that I would devote a whole post on this little [b\wtch].
Long story short about this concept:
Any function that takes multiple arguments, can live its functional life also as a function with a single argument
I always doubt that maths can help me visualize and understand anything but Wikipedia proved me wrong.
Given a function
f:(X x Y) -> Z , where X x Y the Cartesian product of X and Y
**currying** constructs a new function
h: X -> (Y -> Z).
———- This is art! ——————-
| That is, h takes an argument from X and returns a function that maps Y to Z.
| It is defined by
|
| h(x)(y)=f(x,y)
|
| for x from X and y from Y. We then also write
|
| curry(f)=h
———- ——— so prettyyyyy ——— ——————
For example:
def product(a: Int, b: Int): Int = a*b
def curry(f: (Int, Int) => Int) = (a: Int)=> (b:Int) =>f(a,b)
val curriedProduct = curry(product)
curriedProduct(2)(3)
Voilà!
It is simple example, but it was enough to help me get started. Then I finally understood in the end the course, the book and all the google results I found. Sometimes googling “simple” is just not simple enough…
Currying is cool but the weekend’s much cooler, so
bis Monntag :)