Threepenny is a Haskell GUI framework that uses the web browser as a display. It is designed for easy setup across different operating systems. Threepenny includes built-in support for functional reactive programming (FRP).
Questions tagged [threepenny-gui]
55 questions
1
vote
1 answer
Monad: [UI Element] vs [Element]
In the following code sample i tried to create a box with a number of select elements and combine their selection into a list of values using behaviors. (code compiles/runs in ghci with just threepenny-gui)
{-# LANGUAGE RecursiveDo #-}
module…
CryptoCamel
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1
vote
1 answer
How to obtain the string value of an Element?
I want to do something like this:
getValue :: Element -> String
getValue x = do
v <- get UI.value x
v
However, an error is thrown; the expected type of get UI.value x is [String] but the actual type is UI String?
But if I change the type…
allidoiswin
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1
vote
1 answer
How to read data from a table in threepenny-gui?
Let's say I want every to be an object, with its children to be the fields of that object. So I'm looking for something like this:
getListFromTable :: Window -> Element -> [Thing]
getListFromTable w table = do
rows <-…
allidoiswin
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1
vote
1 answer
How to reload updated file in Threepenny-gui 0.6?
The Threepenny-gui changelog (https://hackage.haskell.org/package/threepenny-gui-0.6.0.1/changelog) reads: "The functions loadFile and loadDirectory have been removed, as I felt that the jsStatic option is sufficient for most use cases."
My question…
Maarten Faddegon
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0 answers
Using FRP and IORef in threepenny-gui
I have a little example using IORef in threepenny-gui (TPG):
testIORef :: IORef String -> Window -> UI ()
testIORef ref window = void $ do
return window # set title "Test IORef"
inCell <- UI.input
outCell <- UI.input
-- When value…
b1g3ar5
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1
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2 answers
Using IORef in threepenny gui
I'm trying to set an IORef in threepenny-gui but I can't get it to work. In my app the IORef itself will be more complicated and not itself be displayed - but this example demonstrates the problem I think.
Here is my try:
testIORef2 :: IORef String…
b1g3ar5
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- 9
1
vote
1 answer
Accumulating events with a resettable initial value
I need a function like accumB, but I would like the initial value to be a Behavior instead of a constant. When the initial value changes, the accumulator should 'reset' and start accumulating from that value. Concretely, for the following code and…
int3
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1
vote
1 answer
using threepenny-gui/reactive in client/server programming
I am trying to figure out how to use Haskell threepenny-gui with its reactive functionality to write a program that lets
the user select an item from a listBox
send the selection to an external server
get back a list of results from the…
haroldcarr
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0 answers
How can I compile an existing project of Haskell that has threepenny-gui library on windows?
threepenny-gui: GUI framework that uses the web browser as a display.
Daniel Salgado
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0
votes
1 answer
Getting Errors when trying to test threepenny-gui
i want to try out the threepenny-gui package for haskell.
So i run
cabal install threepenny-gui
... without any problems
So i tried the following example:
module Main where
import qualified Graphics.UI.Threepenny as UI
import …
Xlaech
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