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> Since this is impossible in imperative languages, I can't give you a comparison. I'll bite. Here's foldr() in JavaScript, written in an imperative style:
by RodgerTheGreat 11y ago
> Since this is impossible in imperative languages, I can't give you a comparison.
I'll bite. Here's foldr() in JavaScript, written in an imperative style:
function foldr(func, list) {
var r = [];
for(var index = list.length-1; index >= 0; index--) {
r = func(list[index], r);
}
return r;
}
It isn't defined via pattern matching, but it's absolutely a higher-order function. Functional programming is a collection of ways of thinking about problem solving, and it can be applied to any language.
- Bognar 11y agoAlso, for C# IEnumerables, .Select() is map and .Aggregate() is reduce.
- Kenji 11y agoI like what you are doing here. Since I've been introduced to Haskell, I wondered about functional programming in JavaScript. To my surprise, JavaScript is versatile enough to support a lot of functional concepts!
- Nemcue 11y agoI can recommend flicking through https://leanpub.com/javascript-allonge/read https://leanpub.com/javascript-allonge/read -- it's a really good book on functional programming in JS. Ends up doing Ycombinators, trampolining etc.
- braythwayt 11y agoActually, the original version of this book is no longer for sale. The link for the updated free version is here: https://leanpub.com/javascriptallongesix/read https://leanpub.com/javascriptallongesix/read Or, if you want to buy it in other formats, here: https://leanpub.com/javascriptallongesix https://leanpub.com/javascriptallongesix
- agumonkey 11y agoAll these languages have a similar enough semantic core which if you remove assignments and use mostly closures/hof you end up with a syntactically heavy[1] untyped ML (sic). {Coffee,Live}script comes to mind. [1] remove return, curly braces .. with ES6 unpacking/pseudo-pattern-matching and let, you're half way there.
- okasaki 11y agoNo idea why the author thinks it's impossible. I mean, C stdlib comes with qsort. Here's a map in C void *map(void *in, void (*f)(void *src, void *dst), size_t size, size_t in_s, size_t out_s) { void *out = malloc(size * out_s); for(size_t i = 0; i < size; i++) f(in + (i * in_s), out + (i * out_s)); return out; }