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What is the meaning and difference between subject, user and principal?
...ntext of security frameworks, a few terms commonly occur subject , user and principal , of which I have not been able to find a clear definition and the difference between them.
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How to check iOS version?
...lable(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion] in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to...
Is it possible to set a number to NaN or infinity?
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On python >= 2.6, you can just use math.isnan() and math.isinf()
– Agos
May 9 '11 at 10:21
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Seeking clarification on apparent contradictions regarding weakly typed languages
I think I understand strong typing , but every time I look for examples for what is weak typing I end up finding examples of programming languages that simply coerce/convert types automatically.
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Cookies on localhost with explicit domain
...sic thing about cookies. On localhost, when I set a cookie on server side and specify the domain explicitly as localhost (or .localhost). the cookie does not seem to be accepted by some browsers.
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MYSQL OR vs IN performance
... not believe people who give their "opinion", science is all about testing and evidence.
I ran a loop of 1000x the equivalent queries (for consistency, I used sql_no_cache):
IN: 2.34969592094s
OR: 5.83781504631s
Update:
(I don't have the source code for the original test, as it was 6 years ago, ...
`testl` eax against eax?
I am trying to understand some assembly.
8 Answers
8
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Is short-circuiting logical operators mandated? And evaluation order?
Does the ANSI standard mandate the logical operators to be short-circuited, in either C or C++?
7 Answers
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Difference between “or” and || in Ruby? [duplicate]
What's the difference between the or and || operators in Ruby? Or is it just preference?
8 Answers
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Temporarily put away uncommitted changes in Subversion (a la “git-stash”)
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When I've got uncommitted changes from one task in my working copy and I need to switch to another task, I do one of two things:
Check out a new working copy for the second task.
or
Start a branch:
workingcopy$ svn copy CURRENT_URL_OF_WORKING_COPY SOME_BRANCH
workingcopy$ svn switch SOME...