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Why isn't ProjectName-Prefix.pch created automatically in Xcode 6?
Why isn't ProjectName-Prefix.pch created automatically in Xcode 6 ?
8 Answers
8
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Java generics - why is “extends T” allowed but not “implements T”?
I wonder if there is a special reason in Java for using always " extends " rather than " implements " for defining bounds of typeparameters.
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What is the difference between and ?
...is a thematic grouping of content. Each section should be identified, typically by including a heading (h1-h6 element) as a child of the <section> element.
Examples of sections would be chapters, the various tabbed pages in a tabbed dialog box, or the numbered sections of a thesis. A Web site...
What's the role of GetHashCode in the IEqualityComparer in .NET?
...bjects - so the hash code is not necessarily unique.
A dictionary is a really cool data structure that trades a higher memory footprint in return for (more or less) constant costs for Add/Remove/Get operations. It is a poor choice for iterating over though. Internally, a dictionary contains an arr...
EC2 instance has no public DNS
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answered Jan 6 '14 at 7:32
slayedbyluciferslayedbylucifer
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Floating point vs integer calculations on modern hardware
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From my experience, there are many, many variables to performance...especially between integer & floating point math. It varies strongly from processor to processor (even within the same family such as x86) because different processors have different "pipeline" lengths. Also, some operations ...
LINQ Single vs First
...should NOT use one, when you mean the other.
Note: In my code, I will typically use FirstOrDefault() and SingleOrDefault() but that's a different question.
Take, for example, a table that stores Customers in different languages using a Composite Key ( ID, Lang ):
DBContext db = new DBContext();
Cust...
Class does not implement its superclass's required members
... I updated to Xcode 6 beta 5 today and noticed I received errors in nearly all of my subclasses of Apple's classes.
4 Answe...
Reasons for using the set.seed function
...he set.seed function in R, before starting the program. I know it's basically used for the random number generation. Is there any specific need to set this?
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Error: Jump to case label
...code, if foo equals 1, everything is ok, but if it equals 2, we'll accidentally use the i variable which does exist but probably contains garbage.
switch(foo) {
case 1:
int i = 42; // i exists all the way to the end of the switch
dostuff(i);
break;
case 2:
dostuff(i*2); // i is ...