a transformation of a function into a corresponding function in a more general context.
Questions tagged [lifting]
84 questions
0
votes
1 answer
Is there any way to "lift" a constructor?
Assume I have a function (plusOne in the example below) that only accepts and returns an Int. But I don't have an Int; instead, I have a Maybe Int; and if this Maybe Int contains a value then I want to pass it to plusOne and get a Just of whatever…
user4385532
0
votes
1 answer
Changing the displayed value of react-select by clicking on an external component in React
From one array, I have it displayed as a list on one component(Box.js) and stored in a react-select in another component(Search.js). Both of them are a same level children belonging to a parent component(trial.js).
Ultimately, I want to display the…
episodewon
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1 answer
scala quasiquotes string variable lifting in multiple steps
this is what i want:
scala> var x:Int = 10
x: Int = 10
scala> var y:Int = 20
y: Int = 20
scala> val ret = q"return $x>$y"
ret: universe.Return = return 10.$greater(20)
scala> val result1 = toolbox.compile(ret)()
result1: Any = false
But the…
Pankaj
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Scala: what does _ represent in this case
I'm reading a tutorial for demonstration about lifting method in Scala. Here is the code for basic class:
case object None extends Optional[Nothing]
case class Presenter[+A](get: A) extends Optional[A]
trait Optional[+A] {
def map[B](f: A => B):…
Trần Kim Dự
- 5,872
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0
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2 answers
Scala lift from List[A] to List[Option[A]]
In scala, how can i create a general purpose function to perform the following operation:
f: List[A] ==> List[Option[A]]
raul ferreira
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Haskell : "lifting" a data type to a function
Somehow, I'm still trying to build an intuition on what can I express in Haskell and what not.
I have my own (simple) matrix type and I'm wondering if it would be possible to somehow "lift" it to a function so as to make sense of the usual math…
MASL
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Haskell: writing a function such that it can be lifted to work on lists
I have the following 2 functions:
import qualified Data.Text as T
noneOnEmptyA :: T.Text -> T.Text
noneOnEmptyA txt | T.null txt = "None."
| otherwise = txt
noneOnEmptyB :: [T.Text] -> [T.Text]
noneOnEmptyB txts | null txts =…
the-konapie
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1 answer
Type constraints for polymorphic functions like lift
So I have this code
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
import MonadA
data A = A
newtype MonadA a => MyStateT a b { runMyStateT :: StateT A a b }
deriving (Functor, Applicative, Monad, MonadIO, MonadState A)
instance MonadTrans…
jakubdaniel
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Pipes.Safe - how to use mapM
I have the following code with a pipe which is ok without the second pipe (>-> P.mapM ( fillMD5)). fillMD5 is an operation a -> IO a.
runSafeT $ runEffect $
every (senseRecursive5 startfpo)
>-> P.mapM ( fillMD5)
>-> P.map…
user855443
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