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Correct way to use get_or_create?
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@zypro It's like create(), create object and save it all in one step and doesn't need any save()
– Amin Mir
Jun 19 at 6:05
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RabbitMQ and relationship between channel and connection
... a Channel are serialized, with only one thread being able to run a
command on the Channel at a time. Even so, applications should prefer
using a Channel per thread instead of sharing the same Channel across
multiple threads.
There is no direct relation between Channel and Queue. A Channel ...
Why is the use of tuples in C++ not more common?
...obody seem to use tuples in C++, either the Boost Tuple Library or the standard library for TR1? I have read a lot of C++ code, and very rarely do I see the use of tuples, but I often see lots of places where tuples would solve many problems (usually returning multiple values from functions).
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Swapping two variable value without using third variable
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*x ^= *y;
}
}
Why the test?
The test is to ensure that x and y have different memory locations (rather than different values). This is because (p xor p) = 0 and if both x and y share the same memory location, when one is set to 0, both are set to 0.
When both *x and *y are 0, all o...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...y ways to do this. This answer starts with what is quickly becoming the standard method, but also includes older methods and various other methods from answers to similar questions scattered around this site.
tmp <- data.frame(x=gl(2,3, labels=letters[24:25]),
y=gl(3,1,6, labe...
Clear the cache in JavaScript
....reload(true) to reload the current page. It will ignore any cached items and retrieve new copies of the page, css, images, JavaScript, etc from the server. This doesn't clear the whole cache, but has the effect of clearing the cache for the page you are on.
However, your best strategy is to vers...
JavaScript ternary operator example with functions
...else syntax because I don't like to sacrifice readability - I'm old-school and I prefer my braces.
The full if/then/else format is used for pretty much everything. It's especially popular if you get into larger blocks of code in each branch, you have a muti-branched if/else tree, or multiple else/...
Correct way to add external jars (lib/*.jar) to an IntelliJ IDEA project
...en creating a new Java project in IntelliJ IDEA, the following directories and files are created:
9 Answers
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Verify if a point is Land or Water in Google Maps
..and then Google-maps "divide the waters from the waters"
18 Answers
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Reading specific lines only
... loop to read a file, but I only want to read specific lines, say line #26 and #30. Is there any built-in feature to achieve this?
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