jay: > Don Stewart [EMAIL PROTECTED]: > >jay: > >> I also have constants that are too large to compile. I am resigned to > >> loading them from data files--other solutions seem even worse. > ... > >> Data.Binary eases the irritation somewhat. > > > >Did you try bytestring literals (and maybe parsing them in-memory with > >Data.Binary)? > > That didn't occur to me, since neither of my large constants includes > strings.... I think you're suggesting that each constant could appear in > the source as a long bytestring and be deserialized into the data > structure. If that works, it should improve the startup time, but it's > still not as nice as simply compiling it straight up. > > I'll try it.
Here's an example, which stores a Data.Map in a gzip-compressed bytestring literal (a C string literal in the compiled code). The Map is reconstructed on startup. {-# LANGUAGE OverloadedStrings #-} import Data.Binary import qualified Data.Map as M import qualified Data.ByteString.Char8 as S import Data.ByteString.Lazy import Codec.Compression.GZip -- -- this is a gzip compressed literal bytestring, storing a binary-encoded Data.Map -- mytable = "\US\139\b\NUL\NUL\NUL\NUL\NUL\NUL\ETXEN\219\SO\194 \f\197\224\188\196\CAN\227\US\224\171~\NAKc\GS4ce\161`\178\191\215(\176\190\180\167\231\210\n\241\171\203\191\ti\157\217\149\249< \ENQ\214\&9>\202\162\179a\132X\233\ESC=\231\215\164\SYN\157\DC2D\226*\146\174o\t\167\DLE\209\"i_\240\193\129\199<W\250nC\CAN\212\CAN\162J\160\141C\178\133\216;[EMAIL PROTECTED]&7\rH\222\FSW\130\&7D\197\NUL\164\&0U\193\186\t\186o\228\180~\NUL\a6\249\137#\SOH\NUL\NUL" main = print =<< M.lookup "ghc" m where -- build the table from the bytestring: m :: M.Map String (Maybe String) m = decode . decompress . fromChunks . return $ mytable Running it: $ ./A Just "dinosaur!" :) Important to use a bytestring, since that gets compiled to a C string literal (and not messed with by the simplifier). -- Don _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users