Let's not make this like reddit where there's scores of people who have nothing to do but complain about something they've already seen.
If it's interesting, it's interesting. If it's not worthy of being seen again, it won't be upvoted. By all means link to the previous discussion, but quit the whining.
A while ago I wrote a Haskell compiler for a simple functional language that uses the JIT features of LLVM in order to make the Haskell-level "compile" function lazy in the term being compiled. Quite a fun trick I thought: https://github.com/batterseapower/productive-compiler/blob/m...
The shallow DSL in the LLVM monad is really nice, it looks almost like the IR itself but you can abstract over it and compose it with other code. DSLs are often overlooked when talking about monad use cases.
For the extra curious, here's a little Parser (untested, poor design, but generally the right idea)
newtype Parser a = Parser { unParser :: MaybeT (State String) a }
deriving ( Functor, Applicative, Alternative,
Monad, MonadPlus, MonadTrans,
MonadState String )
-- why write boilerplate when the
-- compiler will for you?
runParser :: Parser a -> String -> Maybe a
runParser input = flip evalStateT input . runMaybeT
-- | Parses a single character if it passes a predicate
satisfy :: (Char -> Bool) -> Parser Char
satisfy p = do
(c:cs) <- get
guard (p c)
put cs
return c
char :: Char -> Parser Char
char c = satisfy (== c)
-- | Parses a whole string
string :: String -> Parser String
string = mapM char
-- | Converts a parser to be surrounded by parentheses
parens :: Parser a -> Parser a
parens p = char '(' *> p <* char ')'
If you're not curious about haskell, I suspect that parser is going to be very difficult to grok.
At least a basic understanding of haskell (or similar) is going to be required to appreciate it, and at that point you're obviously someone who was curious enough to have the knowledge to understand it to begin with.
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[ 0.24 ms ] story [ 40.8 ms ] threadIf it's interesting, it's interesting. If it's not worthy of being seen again, it won't be upvoted. By all means link to the previous discussion, but quit the whining.
At least a basic understanding of haskell (or similar) is going to be required to appreciate it, and at that point you're obviously someone who was curious enough to have the knowledge to understand it to begin with.