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QuestionRe: Exceptions Pin
Eddy Vluggen18-Jan-22 19:32
professionalEddy Vluggen18-Jan-22 19:32 
AnswerRe: Exceptions Pin
lmoelleb18-Jan-22 20:40
Memberlmoelleb18-Jan-22 20:40 
GeneralRe: Exceptions Pin
Eddy Vluggen19-Jan-22 0:40
professionalEddy Vluggen19-Jan-22 0:40 
GeneralRe: Exceptions Pin
lmoelleb19-Jan-22 0:48
Memberlmoelleb19-Jan-22 0:48 
GeneralRe: Exceptions Pin
Eddy Vluggen19-Jan-22 1:12
professionalEddy Vluggen19-Jan-22 1:12 
AnswerRe: Exceptions Pin
Eddy Vluggen18-Jan-22 18:02
professionalEddy Vluggen18-Jan-22 18:02 
AnswerRe: Exceptions Pin
jschell23-Jan-22 7:32
Memberjschell23-Jan-22 7:32 
Questionnecessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff16-Jan-22 2:39
mveBillWoodruff16-Jan-22 2:39 
C# >= 4

Curious to know if you've had to deal with the issues described here.

1) assume you have a generic method of Type T

2) in that method a Func<IEnumerable<T>, IEnumerable<T>> is called on an IEnumerable of T

3) the result of calling the func is in a variable 'temp ... when you examine 'temp in the Command Window at run-time after hitting a break-point:
> ? temp
{System.Linq.Enumerable.WhereListIterator<int>}
    Current: 0
    Results View: Expanding the Results View will enumerate the IEnumerable
> ? temp == null
false
> ? temp == default
false
> ? temp is null
false
> ? temp.Any()
false
> ? temp.Count()
0
4) in the case where the Func call results in no content (no items)

4a) you want to evaluate whether 'temp has any "items" ... i.e., has a Count of #0 (as shown above)

4b) but, you do not want to trigger iteration/enumeration of 'temp by calling Count()

I have read that .Any() will not cause iteration in this very interesting SO thread: [^].

And, on the same thread: [^]: is mention of a new C#6 Linq function 'TryGetNonEnumeratedCount
«The mind is not a vessel to be filled but a fire to be kindled» Plutarch

GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
harold aptroot16-Jan-22 3:21
Memberharold aptroot16-Jan-22 3:21 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff16-Jan-22 5:14
mveBillWoodruff16-Jan-22 5:14 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
harold aptroot16-Jan-22 6:56
Memberharold aptroot16-Jan-22 6:56 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff16-Jan-22 18:22
mveBillWoodruff16-Jan-22 18:22 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
Richard Deeming16-Jan-22 22:45
mveRichard Deeming16-Jan-22 22:45 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff18-Jan-22 1:19
mveBillWoodruff18-Jan-22 1:19 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
Richard Deeming18-Jan-22 1:41
mveRichard Deeming18-Jan-22 1:41 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff18-Jan-22 3:08
mveBillWoodruff18-Jan-22 3:08 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
Richard Deeming18-Jan-22 6:17
mveRichard Deeming18-Jan-22 6:17 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff19-Jan-22 13:58
mveBillWoodruff19-Jan-22 13:58 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
Richard Deeming19-Jan-22 21:43
mveRichard Deeming19-Jan-22 21:43 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff20-Jan-22 4:26
mveBillWoodruff20-Jan-22 4:26 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
harold aptroot16-Jan-22 22:48
Memberharold aptroot16-Jan-22 22:48 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff18-Jan-22 0:49
mveBillWoodruff18-Jan-22 0:49 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
jschell23-Jan-22 7:40
Memberjschell23-Jan-22 7:40 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
BillWoodruff25-Jan-22 3:58
mveBillWoodruff25-Jan-22 3:58 
GeneralRe: necessity to use .Any() to check if an IEnumerable<T> result has no items without iterating over it ? Pin
jschell30-Jan-22 6:22
Memberjschell30-Jan-22 6:22 

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