Questions tagged [deferred-execution]
219 questions
8
votes
1 answer
twisted: difference between `defer.execute` and `threads.deferToThread`
What is the difference between defer.execute() and threads.deferToThread() in twisted? Both take the same arguments - a function, and parameters to call it with - and return a deferred which will be fired with the result of calling the function.…
Claudiu
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7
votes
4 answers
Does LINQ deferred execution occur when rendering the view, or earlier?
Given a very basic LINQ that is returned to a MVC view, at what exact point does the deferred execution fire?
In the controller:
public ActionResult Index()
{
var model = _fooService.GetAll();
return View(model);
}
In the model:
@foreach…
JK.
- 21,477
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6
votes
2 answers
Implementing the ‘defer’ statement from Go in Objective-C?
Today I read about the defer statement in the Go language:
A defer statement pushes a function
call onto a list. The list of saved
calls is executed after the
surrounding function returns. Defer is
commonly used to simplify functions
that…
zoul
- 102,279
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6
votes
2 answers
How can i mock or test my deferred evaluation/execution functionality?
I have what could be seen as a bizarre hybrid of IQueryable and IList collections of domain objects passed up my application stack. I'm trying to maintain as much of the 'late querying' or 'lazy loading' as possible. I do this in two ways:
By…
Matt Kocaj
- 11,278
- 6
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- 79
6
votes
3 answers
How to defer a Django DB operation from within Twisted?
I have a normal Django site running. In addition, there is another twisted process, which listens for Jabber presence notifications and updates the Django DB using Django's ORM.
So far it works as I just call the corresponding Django models (after…
blaf
6
votes
5 answers
Cache a Linq Query - is this possible?
So, this may seem like an edge case, but I'm simply wondering if this is possible. What I have is a combination of a static set and deferred set wrapped in an IEnumerable - for example:
public IEnumerable MakeMyQuery()
{
// returns a…
Tejs
- 40,736
- 10
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5
votes
1 answer
How can I iterate over several IEnumerables simultaneously
Assume I have two (or more) IEnumerable with many elements. Every IEnumerable has another type T. The lists can be extreme long and should not be loaded to memory completetly.
IEnumerable ints = getManyInts();
IEnumerable strings =…
matthias.lukaszek
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5
votes
2 answers
How does golang defer work in cycles?
I'm trying to handle reconnections to MongoDB. To do this I try to perform every operation three times (in case it fails with io.EOF)
type MongoDB struct {
session *mgo.Session
DB *mgo.Database
}
func (d MongoDB)…
StTymur
- 69
- 1
- 3
5
votes
1 answer
.NET Force method deferred execution
Consider the following scenario
private static ConcurrentDictionary> CachedData;
where multiple threads access this variable via a method calling
ConcurrentDictionary dic =…
Miguel A. Arilla
- 5,058
- 1
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- 27
5
votes
1 answer
C#, NUnit: How to deal with testing of exceptions and deferred execution
Say we have a method that looks like this:
public IEnumerable GrowAll(this IEnumerable puppies)
{
if(subjects == null)
throw new ArgumentNullException("subjects");
foreach(var puppy in puppies)
yield return…
Svish
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5
votes
1 answer
Python "deferred calculation" programming
This is a two part python question. The first part is about aesthetics and the second is about implementation. A sample of the code I've got working so far is attached at the bottom.
The problem.
I am trying to design a python module / class which…
Richard Green
- 2,037
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5
votes
1 answer
Dart: Is using a zero duration timer the supported way of deferring work to the event loop
I discovered by experimenting that creating a timer with a duration of 0 allows me to defer work into the event queue. I really like this feature, because it allows avoiding a lot of nasty reentrancy issues. Is this intentional functionality that…
Jim Belton
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5
votes
1 answer
Does it make sense for an ASP.NET Web API method to return IQueryable?
I'm working on a project that uses the new Web API and I noticed somebody is returning an IQueryable from a Get method.
My understanding is that IQueryable is useful for improving performance (deferred execution), but I don't think a client on…
Andy West
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4
votes
1 answer
LINQ: using IEnumerable.Count() or IList.Count for better performance
Based on the following code:
var grouped = filters.GroupBy(p => p.PropertyName);
int numOfRowElements = grouped.Count();
foreach (IGrouping filter in grouped)
{
…
Klaus Nji
- 18,107
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4
votes
1 answer
How do you create a python list comprehension of lambdas?
I am trying create a list of lambdas for deferred execution using a list comprehension.
The below is a simple example.
def func_a(message: str) -> None:
print('a: ' + message)
def func_b(message: str) -> None:
print('b: ' +…
OldSchool
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