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Regex - Should hyphens be escaped? [duplicate]
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Correct on all fronts. Outside of a character class (that's what the "square brackets" are called) the hyphen has no special meaning, and within a character class, you can place a hyphen as the first or last character in the range (e.g....
Initializing a static std::map in C++
... Every time I see something like that done with C++, I think of all the horrendous template code that must be behind it. Good example!
– Greg Hewgill
Sep 26 '08 at 10:22
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Troubleshooting “The use statement with non-compound name … has no effect”
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PHP's use isn't the same as C++'s using namespace; it allows you to define an alias, not to "import" a namespace and thus henceforth omit the namespace qualifier altogether.
So, you could do:
use Blog\Article as BA;
... to shorten it, but you cannot get rid of it entirely.
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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
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Without the update-and-join notation (not all DBMS support that), use:
UPDATE QuestionTrackings
SET QuestionID = (SELECT QuestionID
FROM AnswerTrackings
WHERE AnswerTrackings.AnswerID = QuestionTrackings.AnswerID)
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Is there an equivalent to CTRL+C in IPython Notebook in Firefox to break cells that are running?
...errupt the entire iPython Notebook server. This will stop iPython Notebook alltogether, which means it won't be possible to restart or save your work, so this is obviously not a great solution (you need to hit CTRL+C twice because it's a safety feature so that people don't do it by accident). In cas...
Advantages to Using Private Static Methods
When creating a class that has internal private methods, usually to reduce code duplication, that don't require the use of any instance fields, are there performance or memory advantages to declaring the method as static?
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Symbolic links and synced folders in Vagrant
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Virtualbox does not allow symlinks on shared folders for security reasons. To enable symlinks the following line needs to be added to the vm provider config block in the Vagrantfile:
config.vm.provider "virtualbox" do |v|
v.customize ["sete...
Find the most common element in a list
...roups by the item only (via operator.itemgetter). The auxiliary function, called once per grouping during the max computation, receives and internally unpacks a group - a tuple with two items (item, iterable) where the iterable's items are also two-item tuples, (item, original index) [[the items of ...
How to check 'undefined' value in jQuery
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JQuery library was developed specifically to simplify and to unify certain JavaScript functionality.
However if you need to check a variable against undefined value, there is no need to invent any special method, since JavaScript has a typeof operator, which is...
'is' versus try cast with null check
...ing)
{
var x = (string) o;
}
This translates to the following IL:
IL_0000: nop
IL_0001: ldstr "test"
IL_0006: stloc.0 // o
IL_0007: ldloc.0 // o
IL_0008: isinst System.String
IL_000D: ldnull
IL_000E: cgt.un
IL_0010: stloc.1
IL_0011: ldloc....