Difference between revisions of "PropLang"

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Link: http://www.cse.unsw.edu.au/~chak/haskell/ports/
  
Link: http://www.cse.unsw.edu.au/~chak/haskell/ports/
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== Thoughts by ==
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Neil Mitchell
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== The Var concept ==
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This is the low level stuff, on which the library will be built
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data Var a = ...
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data Notify
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get :: Var a -> IO a
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set :: Var a -> a -> IO ()
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addNotify :: Var a -> IO () -> IO Notify
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remNotify :: Notify -> IO ()
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newVar :: a -> IO (Var a)
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== Object layering ==
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textBox-text -< "test"
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filename <- newVar Nothing
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notify filename hatCover
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lbl-text =< with filename $ \x ->
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case x of
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Nothing -> "Select a file"
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Just x -> "Loaded: " ++ x
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where
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(-) :: GtkObject -> GtkProp -> Var a -- ignoring lots of details here
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(-<) :: Var a -> a -> IO ()
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(=<) :: Var a -> Action a -> IO ()
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with :: Var a -> (a -> b) -> Action b

Revision as of 00:29, 18 July 2006

A design for a GUI library which is more like Haskell and less like C.

Link: http://www.cse.unsw.edu.au/~chak/haskell/ports/

Thoughts by

Neil Mitchell

The Var concept

This is the low level stuff, on which the library will be built 

data Var a = ...
data Notify

get :: Var a -> IO a
set :: Var a -> a -> IO ()
addNotify :: Var a -> IO () -> IO Notify
remNotify :: Notify -> IO ()

newVar :: a -> IO (Var a)

Object layering

textBox-text -< "test"
filename <- newVar Nothing
notify filename hatCover
lbl-text =< with filename $ \x ->
                 case x of
                     Nothing -> "Select a file"
                     Just x -> "Loaded: " ++ x


where 

(-) :: GtkObject -> GtkProp -> Var a -- ignoring lots of details here
(-<) :: Var a -> a -> IO ()
(=<) :: Var a -> Action a -> IO ()

with :: Var a -> (a -> b) -> Action b
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