Definition of Foldr. Meaning of Foldr. Synonyms of Foldr

- initial value and the first element. foldr :: (a -> b -> b) -> b -> [a] -> b foldr f z [] = z foldr f z (x:xs) = f x (foldr f z xs) If the list is empty, the...
- defined in terms of a fold such as foldr, which means one can do a map-fold fusion: foldr f z . map g is equivalent to foldr (f . g) z. The implementation...
- can replace this with: sum xs = foldr (+) 0 xs And then the argument is not needed, so this simplifies to sum = foldr (+) 0 which is point-free. Another...
- ++ [x] ++ flatten s treesort :: Ord a => [a] -> [a] treesort = flatten . foldr insert Leaf In the above implementation, both the insertion algorithm and...
- "product") factorial n = foldl (*) 1 [1..n] -- Point-free style factorial = foldr (*) 1 . enumFromTo 1 Using Haskell's Fixed-point combinator allows this...
- (including a set of rules included in GHC's standard libraries that performs foldr/build fusion), unfolding (called "inlining" in more traditional compilers)...
- saw previously can be written as a sequence of functions: factorial n = foldr ((.) . (*)) id [1..n] $ 1 -- factorial 5 == ((1*) .) ( ((2*) .) ( ((3*)...
- 1] # a and b are special identifiers in the foldr macro echo numbers.filter(x => x > 3).deduplicate.foldr(a + b) # 30 Nim has support for product types...
- Scheme implementation above: append :: [a] -> [a] -> [a] append xs ys = foldr (:) ys xs This is essentially a reimplementation of Haskell's ++ operator...
- g x y relates cata to the right fold foldrList of lists via: foldrList :: (a -> b -> b) -> b-> List a -> b foldrList fun b0 = cata (lift fun b0) The definition...