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Getting all types that implement an interface

Using reflection, how can I get all types that implement an interface with C# 3.0/.NET 3.5 with the least code, and minimizing iterations? ...
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How does the keyword “use” work in PHP and can I import classes with it?

...ou want to access those class objects then you can do the following: $smtp_mailer = new SMTPMailer; $mailgun_mailer = new MailgunMailer; It will reference the original class. Some may get confused that then of there are not Similar class names then there is no use of use keyword. Well, you can u...
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convert an enum to another type of enum

...se too. – eRaisedToX Aug 2 '19 at 5:32 add a comment  |  ...
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C++ performance vs. Java/C#

...p of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because of this intermediate step, however I've been told that the latest compilers ("hot spot") can attain this speed or even exceed it. ...
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Difference between Role and GrantedAuthority in Spring Security

...thority as being a "permission" or a "right". Those "permissions" are (normally) expressed as strings (with the getAuthority() method). Those strings let you identify the permissions and let your voters decide if they grant access to something. You can grant different GrantedAuthoritys (permissions...
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How to append rows to an R data frame

... Not knowing what you are trying to do, I'll share one more suggestion: Preallocate vectors of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame. Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, def...
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Filtering collections in C#

... ints that are > than 7, Where returns an // IEnumerable<T> so a call to ToList is required to convert back to a List<T>. List<int> filteredList = myList.Where( x => x > 7).ToList(); If you can't find the .Where, that means you need to import using System.Linq; at the to...
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E11000 duplicate key error index in mongodb mongoose

... null value. In other words, a sparse index is ok with multiple documents all having null values. sparse indexes From comments: Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old an...
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Detecting when the 'back' button is pressed on a navbar

...to work under certain scenarios in iOS 8+. I can't verify that that is actually the case without further details. For those of you however in that situation there's an alternative. Detecting when a view controller is being popped is possible by overriding willMove(toParentViewController:). The basi...
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How to pass a user defined argument in scrapy spider

... The above code is only partially working for me. For eg. If I define domain using self.domain, I'm still not able to access it outside the __init__ method. Python throws a not defined error. BTW, why have you omitted the super call? PS. I'm working wit...