[Haskell-cafe] What is NoPush module?

[Magicloud Magiclouds]

Hi,
  When I compiling happstack with ghc 7, I got an error:
src/Happstack/Server/Internal/Handler.hs:29:8:
    Could not find module `NoPush':
      Use -v to see a list of the files searched for.
  I looked around, there is no clue for the module NoPush, except it
has a function call withNoPush.
  What is it?
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