static constants -- ideas?

Jason Dusek jason.dusek at
Sun Feb 24 02:56:25 EST 2008

  I have an awkward programming problem -- I need to take a
  dictionary, parse it, build a bunch of intermediate lists and
  then make maps and tries out of the list. A "programming
  problem" because it's taken me a fair amount of effort to pull
  together the parser and list generator -- and "awkward"
  because a 69000 item list, [(String, [(String, String)])],
  does not compile under GHC (stack overflow). (It's not likely
  to compile under anything else, either!)

  Members of #haskell have urged me to load the offending
  material from a file; indeed, it only takes ten seconds to
  parse the dictionary and build the lists, sort them and dump
  them back out again -- but it offends my sensibilities. I
  don't want to wait ten seconds to load my dictionary every

  I could use the FFI, then I can make the trie and lists all in
  C. That'd work great. My list likely uses too much RAM now,

  I'm considering one other option though -- I wonder if I can
  build large constants in GHC Core? If anybody has tried it --
  or found some other way to make big huge constants in Haskell
  -- I would sure like to know about it.

  On another note, I am extremely curious about the difference
  between statically compiling a list and building it at
  runtime. I find it hard to wrap my head around the fact that I
  can build the list at runtime in a short time, but can not
  compile it without eating all of my machine's RAM. Is it due
  to laziness, maybe? Well, no -- because I subject the whole
  list to a sort. It's not just streaming records in from one IO
  handle and out another.


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