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subtle differences between JavaScript and Lua [closed]
...= operators are of lower precedence than >, >=, <, <=. In Lua, all comparison operators are the same precedence.
Lua supports tail calls.
UPDATE: JS now supports tail calls.
Lua supports assignment to a list of variables. While it isn't yet standard in Javascript, Mozilla's JS engine ...
ReSharper warns: “Static field in generic type”
Is this wrong? I would assume that this actually has a static readonly field for each of the possible EnumRouteConstraint<T> that I happen to instance.
...
MongoDB Many-to-Many Association
... user document:
{name:"Joe"
,roles:["Admin","User","Engineer"]
}
To get all the Engineers, use:
db.things.find( { roles : "Engineer" } );
If you want to maintain the roles in separate documents then you can include the document's _id in the roles array instead of the name:
{name:"Joe"
,roles:...
How to wait for a BackgroundWorker to cancel?
...Async();
_resetEvent.WaitOne(); // will block until _resetEvent.Set() call made
}
void worker_DoWork(object sender, DoWorkEventArgs e)
{
while(!e.Cancel)
{
// do something
}
_resetEvent.Set(); // signal that worker is done
}
...
boost::flat_map and its performance compared to map and unordered_map
...e, because your cache will not be warm, and your operation will likely be called just once. Therefore you need to benchmark using RDTSC, and time stuff calling them once only.
Intel has made a paper describing how to use RDTSC (using a cpuid instruction to flush the pipeline, and calling it at least...
Best way to replace multiple characters in a string?
...
Replacing two characters
I timed all the methods in the current answers along with one extra.
With an input string of abc&def#ghi and replacing & -> \& and # -> \#, the fastest way was to chain together the replacements like this: text.rep...
Implementing IDisposable correctly
...uld have any unmanaged resources to be freed you should include Finalizer calling Dispose(false), that will allow GC to call Finalizer when doing garbage collection (in case Dispose was not called yet) and properly free unmanaged resources.
– mariozski
May 17 '...
How to convert a String to its equivalent LINQ Expression Tree?
...nking as a Where clause. If necessary, put it inside a list/array just to call .Where(string) on it! i.e.
var people = new List<Person> { person };
int match = people.Where(filter).Any();
If not, writing a parser (using Expression under the hood) isn't hugely taxing - I wrote one similar (a...
Cannot delete or update a parent row: a foreign key constraint fails
... (`advertiser_id`)
REFERENCES `jobs` (`advertiser_id`);
...is actually the opposite to what it should be. As it is, it means that you'd have to have a record in the jobs table before the advertisers. So you need to use:
ALTER TABLE `jobs`
ADD CONSTRAINT `advertisers_ibfk_1` FOREIGN KEY...
Where does Scala look for implicits?
...
Implicits in Scala refers to either a value that can be passed "automatically", so to speak, or a conversion from one type to another that is made automatically.
Implicit Conversion
Speaking very briefly about the latter type, if one calls a method m on an object o of a class C, and that class d...