To "reify" means to take an abstract concept and make a concrete representation out of it. For example, in Lisp lambdas allow you to reify the concepts of procedure abstraction and application.
Questions tagged [reify]
30 questions
260
votes
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Getting associated type synonyms with template Haskell
Can Template Haskell find out the names and/or the declarations of the associated type synonyms declared in a type class? I expected reify would do what I want, but it doesn't seem to provide all the necessary information. It works for getting…
Antal Spector-Zabusky
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21
votes
1 answer
What do "idealTree" and "reify" mean in the context of npm?
When creating a react app via "npx create-react-app [app_name]" I noticed the console log something like [#############] idealTree:[package-name]... and then the same thing with "reify" instead of "idealTree". When I search what these terms mean I…
Zakareya Alatoli
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votes
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Get a Haskell record's field names as a list of strings?
Say I have the following:
data Rec = Rec {
alpha :: Int,
beta :: Double,
phi :: Float
}
sample = Rec 1 2.3 4.5
I understand Template Haskell & the reify function can get me the record's field names. That is:
print $(f sample) -->…
user1002430
15
votes
1 answer
Is it possible to get a type of any expression using Template Haskell?
Given an expression foo, I could declare a top-level function
bar = foo
and get the type of foo as Type by reifying bar:
case reify 'bar of
VarI _ t _ _ -> t
Is there a direct way of getting the type of foo, without creating the redundant…
Petr
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npm install hangs at " reify:tailwindcss: timing build:queue Completed in 141ms"
It always hangs at the same place: reify:tailwindcss: timing build:queue Completed in [number]ms
I've even tried just walking away and leaving it overnight to no avail. What's really frustrating is this worked on another project for me about a week…
aylnon
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10
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1 answer
How to get the declaration of a function using `reify`?
Function reify allows me to look up information about a given name. For a function the returned value is VarI:
data Info = ... | VarI Name Type (Maybe Dec) Fixity | ...
Here I can examine the function's type, and I'd also like to examine its…
Petr
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7
votes
2 answers
How to reify Prolog's backtracking state to perform the same task as "lazy seq" from Clojure?
Here is a quicksort algorithm for numbers written in Clojure. It is basically the quicksort algorithm found in "The Joy of Clojure", 2nd edition, page 133. I modified it slightly for (hopefully) better readability, because the original felt a bit…
David Tonhofer
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Is there a way how to enumerate all functions in a module using Template Haskell?
While I can use reify to get information about most other syntactic constructs, I couldn't find anything that would give some information about a module.
Petr
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6
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Can some explain the reflection package API in *very* simple terms?
I'm having a hard time understanding the documentation/examples out there describing the reflection package. I'm an imperative-programming veteran but a Haskell newb. Can you walk me through a very simple introduction?
Package:…
AgentLiquid
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Use a clojure macro to automatically create getters and setters inside a reify call
I am trying to implement a huge Java interface with numerous (~50) getter and setter methods (some with irregular names). I thought it would be nice to use a macro to reduce the amount of code. So instead of
(def data (atom {:x nil}))
(reify…
Arthur Edelstein
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6
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2 answers
Explanation for reification in RDF
I am have understand the basics of reification in RDF. Two clearly explanations are given here: explanation 1
and explanation 2. If you observe carefully, actually we can present in the sentence "Earth is round" RDF triple where as "Scientist…
Nusrat
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5
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1 answer
Provide a constructor with Clojure reify
When using reify in Clojure, how can I provide an expression for the constructor?
Alternatively, how can I pass arguments to the base class constructor?
pauldoo
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5
votes
1 answer
How to reify Java Interfaces with overloaded method?
I am trying to 'implement' the following Java interface from JGroups with reify.
public interface MessageListener extends StateListener {
/**
* Called when a message is received.
* @param msg
*/
void receive(Message msg);
…
javahippie
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4
votes
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Clojure: implementing stateful Java interface
Kafka Streams has an interface, Processor, the implementation of which is stateful. An example implementation given in the developer guide is:
public class WordCountProcessor implements Processor {
private ProcessorContext…
Tianxiang Xiong
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3
votes
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How to override a method of an existing object?
The object was created with reify and I need to override one of its method. The only way I found is to use classic OO decorator with another use of reify. Is there any other way?
Pol
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