Fun.js – Just a sketch
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Fun.js – Just a sketch
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Re: Fun.js – Just a sketch
#2What would you say are the skills required to fully understand this?
Re: Fun.js – Just a sketch
#3What would you say are the skills required to fully understand this?
It's a pretty fast paced intro to a lot of functional programming concepts. You can read a guide like learnyouahaskell.com, which will take you on a gentler ride.
Re: Fun.js – Just a sketch
#4What would you say are the skills required to fully understand this?
Possibly not too high. Try using map, filter, and reduce on some example problems and you'll pick it up fairly quickly. Project Euler makes for decent fodder. When you've successfully managed to apply them then try rewriting the functions (delete the implementation you are using - such as the library above - and rewrite it from scratch).
Re: Fun.js – Just a sketch
#5Sorry to nitpick, but I got hung up right at the beginning with his "truthy" function.
It returns true on values such as NaN, zero, or an empty string. I don't think I'm alone in considering those to be "falsy" values, for example:
Re: Fun.js – Just a sketch
#6A lot of these examples are wrong...
function double(n) { return 2*n; }
map(double, [1,2,3])
//=> [1, 4, 9]
function greaterThan(l, r) {
return l > r;
}
greaterThan(5, 100);
//=> true
maybeGT(5)(10000000);
//=> false
schonfinkel(function(a1,a2) {return [a1,a2];})(1)(2);
//=> [1, 2]
Edit: since i'm going to complain I might as well say something nice as well. I did like this article example correctness aside, and I hadn't seen that implementation of pipeline before! Much awesome. =)
Re: Fun.js – Just a sketch
#7Good read, nice intro into functional programming. Thanks!
Re: Fun.js – Just a sketch
#8Sorry to nitpick, but I got hung up right at the beginning with his "truthy" function. It returns true on values such as NaN, zero, or an empty string. I don't think I'm alone in considering those to be "falsy" values, for example: http://www.sitepoint.com/javascript-truthy-falsy/
Technically the are JS falsey, but I choose not to treat them that way. I rarely want to treat the result of a calculation as a boolean condition. However, I often want to know if a calculation isNaN or isEmpty. Just because something is falsey doesn't mean it should be treated that way universally.
Re: Fun.js – Just a sketch
#9Just a note - forEach doesn't work in IE8. I wonder at what point can we stop caring about that?
Re: Fun.js – Just a sketch
#10Sorry to nitpick, but I got hung up right at the beginning with his "truthy" function. It returns true on values such as NaN, zero, or an empty string. I don't think I'm alone in considering those to be "falsy" values, for example: http://www.sitepoint.com/javascript-truthy-falsy/
Technically the are JS falsey, but I choose not to treat them that way. I rarely want to treat the result of a calculation as a boolean condition. However, I often want to know if a calculation isNaN or isEmpty. Just because something is falsey doesn't mean it should be treated that way universally.
Right on, I get that, but truthy(NaN) and truthy(5) both return true, so you still don't know if the calculation isNaN.
Btw, I should have said first: I love the article in general and it's great to see these techniques becoming more mainstream in javascript. Thank you!