I see many comments saying that the book implements the C compiler in ocaml. In the introduction the author states that the book actually uses pseudo code so you are actually free to implement it in any language. The only recommendation is that you use a language with pattern matching because the pseudo code makes heavy use of it. The reference implementation is in ocaml.
Question for HN, pattern matching is defined as “runtime type/value checking”, is that correct? Is duck typing the pseudo-unsafe alternative? (Not unsafe as in accessing unsafe memory, but as in throwing exceptions if the duck-typed function doesn’t exist on the current type) Can C handle both? Coming from a static type system like rust and c#, i’m doing alot of “if this is a duck, duck.quack()” and i’m looking for f…
data Tree a = Leaf a | Branch (Tree a) (Tree a)
fromList :: [a] -> Tree [a]
fromList = Leaf
toList :: Tree [a] -> [a]
toList (Leaf x) = x
toList (Branch (Leaf x) r) = x ++ toList r
toList (Branch (Branch l1 l2) r)
= toList (Branch l1 (Branch l2 r))
append :: Tree [a] -> Tree [a] -> Tree [a]
append = Branch
Since a compiler is all about tree manipulation, support for tree pattern matching should be a boon.
[0]: http://h2.jaguarpaw.co.uk/posts/demystifying-dlist/
[1]: https://en.wikipedia.org/wiki/Joel_Spolsky#Schlemiel_the_Pai...