Unanswered Questions
27
votes
0answers
2k views
Why (or why not) are existential types considered bad practice in functional programming?
What are some techniques I might use to consistently refactor code removing the reliance on existential types? Typically these are used to disqualify undesired constructions of your type as well as to ...
10
votes
2answers
495 views
In-memory datastore in Haskell
I want to implement an in-memory datastore for a web service in Haskell. I want to run transactions in the STM monad.
When I google hash table steam Haskell I only get this: Data. BTree. HashTable. ...
9
votes
0answers
284 views
How to implement a branch-and-bound in a functional programming language?
I am trying to write a branch and bound search on the set of all functions f: D -> R, where the domain size is small (|D| ~ 20) and the range is much bigger (|R| ~ 2^20). Initially, I came up with the ...
8
votes
1answer
795 views
Useful design patterns for working with FragmentManager on Android
When working with fragments, I have been using a class composed of static methods that define actions on fragments. For any given project, I might have a class called FragmentActions, which contains ...
6
votes
1answer
110 views
Are “skip deltas” unique to svn?
The good folks who created the SVN version control system use a structure they refer to as "skip deltas" to store the revision history of files internally. A revision is stored as a delta against an ...
6
votes
0answers
140 views
Using uniqueness types to implement safe parallelism
I've been interested in uniqueness types as an alternative to monads in pure functional languages for some time; unfortunately, this is kind of an esoteric area of CS research and online resources ...
6
votes
1answer
153 views
Heuristic Approach for Flexible DIFF Implementation
I have created a DIFF implementation to compare document revisions at work. It is based on An O(ND) Difference Algorithm and Its Variations.
One thing that has become important is to take the list ...
5
votes
1answer
635 views
Attachment handling for web application with Jackrabbit
I need to manage attachments on my Spring web application and I thought to use an open source repository.
My app it's a job approval system using J2EE / SPRING 3 Framework and Postgress DB to allow ...
5
votes
4answers
373 views
Adding field to the class at runtime - design pattern
Imagine your customer want's to have a possibility to add new property (e.g. color) to product in their eshop in their CMS.
Instead of having properties as fields:
class Car extends Product {
...
4
votes
0answers
39 views
Why does the new ADT create a static inner class Fragment by default?
Honestly, I can't help but feel that this is done merely to confuse newcomers. Most of the errors on Stack Overflow by complete Android newbies mostly stem from that they have a static inner class ...
4
votes
0answers
89 views
How to represent hard-to-calculate “properties” of “objects” in functional code?
I have a polyline "class" in my Clojure program, which is represented by a vector of points. (It's not really a class or anything.)
The polyline's length (in the geometric sense) is something that is ...
4
votes
3answers
124 views
Using mocks to set up object even if you will not be mocking any behavior or verifying any interaction with it?
When building a unit test, is it appropriate to use a mocking tool to assist you in setting up an object even if you will not be mocking any behavior or verifying any interaction with that object?
...
4
votes
1answer
232 views
What are the benefits of Android way of “saving memory” - explicitly passing Context objects everywhere?
Turned out, this question is not easy to formulate for me, but let's try.
In Android, pretty much any UI object depends on a Context, and has defined lifetime. Android can also destroy and recreate UI ...
4
votes
1answer
878 views
Help with complex MVVM (multiple views)
I need help creating view models for the following scenario:
Deep, hierarchical data
Multiple views for the same set of data
Each view is a single, dynamically-changing view, based on the active ...
4
votes
0answers
3k views
using dbus on Android
I would like to know if it is possible to use DBUS on Android using Java. From what I have been searching till now it appears like there is no DBUS programming support on Android. But then bluetooth ...
