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What is the Swift equivalent to Objective-C's “@synchronized”?
I've searched the Swift book, but can't find the Swift version of @synchronized. How do I do mutual exclusion in Swift?
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What is the difference between float and double?
I've read about the difference between double precision and single precision. However, in most cases, float and double seem to be interchangeable, i.e. using one or the other does not seem to affect the results. Is this really the case? When are floats and doubles interchangeable? What are the d...
How do pointer to pointers work in C?
How do pointers to pointers work in C?
When would you use them?
14 Answers
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What is the difference between UNION and UNION ALL?
...s from the result set but union all returns all rows after joining.
from http://zengin.wordpress.com/2007/07/31/union-vs-union-all/
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How can I convert spaces to tabs in Vim or Linux?
I've looked over several questions on Stack Overflow for how to convert spaces to tabs without finding what I need. There seem to be more questions about how to convert tabs to spaces, but I'm trying to do the opposite.
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How to count TRUE values in a logical vector
In R, what is the most efficient/idiomatic way to count the number of TRUE values in a logical vector? I can think of two ways:
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Google Guice vs. PicoContainer for Dependency Injection
...ck to it if they'd just fix their web sites. It's really confusing now:
http://picocontainer.com which is the most recent, but many pages have formatting issues and a few pages don't work at all. It looks like the pages were auto-converted from the older content.
http://picocontainer.codehaus.o...
Syntax for a single-line Bash infinite while loop
I am having trouble coming up with the right combination of semicolons and/or braces. I'd like to do this, but as a one-liner from the command line:
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YYYY-MM-DD format date in shell script
I tried using $(date) in my bash shell script, however, I want the date in YYYY-MM-DD format.
How do I get this?
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How can I pass a parameter to a Java Thread?
Can anyone suggest to me how I can pass a parameter to a thread?
18 Answers
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