diff options
-rw-r--r-- | entries/fhackett/fib.kk | 83 | ||||
-rw-r--r-- | people.json | 11 |
2 files changed, 94 insertions, 0 deletions
diff --git a/entries/fhackett/fib.kk b/entries/fhackett/fib.kk new file mode 100644 index 0000000..e4d8107 --- /dev/null +++ b/entries/fhackett/fib.kk @@ -0,0 +1,83 @@ + +effect store<k,v> { + fun put(key: k, value: v): () + fun get(key: k): maybe<v> +} + +fun no-store(body: () -> <store<k,v>,div|e> t): <div|e> t { + with handler { + fun get(key) Nothing + fun put(key, value) {} + } in { + body() + } +} + +fun list-store(eq: (k,k) -> total bool, body: () -> <store<k,v>,div|e> t): <div|e> t { + var data := Nil + with handler { + fun get(key) { + data.lookup fn(candidate-key) key.eq(candidate-key) + } + fun put(key, value) { + data := Cons((key, value), data.filter(fn((kk, _)) !kk.eq(key))) + } + } in { + body() + } +} + +fun pair-store(body: () -> <store<int,int>,div|e> t): <console,div|e> t { + var first := 0 + var second := 1 + var idx := 1 + + with handler { + fun get(key) { + if idx == key then Just(second) + else if idx - 1 == key then Just(first) + else Nothing + } + fun put(key, value) { + if key == idx + 1 then { + idx := idx + 1 + first := second + second := value + } else { + println("error: " ++ key.show ++ " := " ++ value.show ++ "; " ++ first.show ++ ", " ++ second.show ++ ", " ++ idx.show) + } + } + } in { + mask<console>(body) + } +} + +fun fib(n: int): <div,store<int,int>> int { + match get(n) { + Just(result) -> result + Nothing -> + match n { + 0 -> 0 + 1 -> 1 + _ -> + val result = fib(n - 2) + fib(n - 1) + put(n, result) + result + } + } +} + +pub fun fib-naive(n: int): div int { + with no-store + fib(n) +} + +pub fun fib-list(n: int): div int { + with list-store(fn(a: int, b: int) a == b) + fib(n) +} + +pub fun fib-pair(n: int): <div,console> int { + with pair-store + fib(n) +} diff --git a/people.json b/people.json index 4561b11..42d580b 100644 --- a/people.json +++ b/people.json @@ -94,6 +94,17 @@ ] }, { + "github": "fhackett", + "name": "Finn Hackett", + "title": "PhD Student, UBC", + "entries": [ + { + "name": "koka-store", + "link": "./entries/fhackett/fib.kk" + } + ] + }, + { "github": "funemy", "name": "Yanze Li", "title": "PhD Student, UBC", |