Re: [xmonad] How to disable history in XMonad.Actions.Search.

On Sun, Sep 20, 2009 at 11:42 AM, Mike Sampson wrote:

Gwern,

On Mon, Sep 21, 2009 at 12:10 AM, Gwern Branwen wrote:

...

Code tip: you could also write '\_ -> []', or just 'const []'.

Yes, my Haskell leaves a lot to be desired. :) I went with const []. Thanks.

...

If you look in Search, you'll see:

{- | Like 'search', but for use with the output from a Prompt; it grabs the   Prompt's result, passes it to a given searchEngine and opens it in a given   browser. -} promptSearchBrowser ∷  XPConfig →  Browser →  SearchEngine →  X () promptSearchBrowser config browser (SearchEngine name site) = mkXPrompt (Search name) config historyCompletion $ search browser site

That is, 'config' is not asked for the history completion function nor is any filter ran upon it; rather, it uses the canned historyCompletion function from XMonad.Prompt.

Ahh. I did browse this file but missed the finer details of that function.

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It's possible to grab the historyFilter from the XPConfig that promptSearchBrowser has access to; if you could test out my attached patch?

Applied. This seems to be working perfectly. When the above historyFilter is used, the history file is still created but contains an empty list. Perfect.

Your assistance is much appreciated. Once again the xmonad mailing list comes through for me.

Many thanks,

Mike

This patch isn't perfect, though. I reflected on it and realized that it doesn't make sense to have invokers of mkXPrompt do the filtering themselves, when mkXPrompt has access to the XPConfig and the Completion functions - one could just write the filtering once, in mkXPrompt, and not every caller. But when I went to add it, I saw that mkXPrompt wraps mkXPromptWithReturn, and the latter calls 'historyFilter conf'! Which mystifies me. I'm now not sure why my patch worked or what to do next: mkXPromptWithReturn ∷ XPrompt p ⇒ p → XPConfig → ComplFunction → (String → X a) → X (Maybe a) mkXPromptWithReturn t conf compl action = do c ← ask let d = display c rw = theRoot c s ← gets $ screenRect · W.screenDetail · W.current · windowset hist ← liftIO $ readHistory w ← liftIO $ createWin d rw conf s liftIO $ selectInput d w $ exposureMask .|. keyPressMask gc ← liftIO $ createGC d w liftIO $ setGraphicsExposures d gc False fs ← initXMF (font conf) let hs = fromMaybe [] $ Map.lookup (showXPrompt t) hist st = initState d rw w s compl gc fs (XPT t) hs conf st' ← liftIO $ execStateT runXP st releaseXMF fs liftIO $ freeGC d gc if successful st' then do liftIO $ writeHistory $ Map.insertWith (λxs ys → take (historySize conf) · historyFilter conf $ xs ++ ys) (showXPrompt t) [command st'] hist Just <$> action (command st') else return Nothing -- gwern