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Double not (!!) operator in PHP
...ings or empty arrays) you will get the boolean value FALSE.
It is functionally equivalent to a cast to boolean:
return (bool)$row;
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The type 'string' must be a non-nullable type in order to use it as parameter T in the generic type
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Use string instead of string? in all places in your code.
The Nullable<T> type requires that T is a non-nullable value type, for example int or DateTime. Reference types like string can already be null. There would be no point in allowing things like ...
What exactly does big Ө notation represent?
I'm really confused about the differences between big O, big Omega, and big Theta notation.
6 Answers
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What is so special about Generic.xaml?
...rrent Windows theme e.g. on Vista using the Aero theme, the dictionary is called Aero.NormalColor.xaml, on XP using the default theme it is Luna.NormalColor.xaml. If the style is not found in the theme dictionary, it looks in Generic.xaml i.e for controls whose look doesn't depend on the theme.
Thi...
Find rows with multiple duplicate fields with Active Record, Rails & Postgres
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User.select(:first,:email).group(:first,:email).having("count(*) > 1").all
(note: not tested, you may need to tweak it)
EDITED to remove id column
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MIME type warning in chrome for png images
... Express as your server as well (VS 2010 SP1).
I 'resolved' my problem locally by editing the project settings (under Web) and changed from the ASP.NET Development Server to IIS on my local machine. I can see that PNG was already defined correctly as an image MIME type and indeed when I hit my loca...
Retrieve filename from file descriptor in C
...fd you have, and make sure st_dev and st_ino are the same.
Of course, not all file descriptors refer to files, and for those you'll see some odd text strings, such as pipe:[1538488]. Since all of the real filenames will be absolute paths, you can determine which these are easily enough. Further, as...
What's the status of multicore programming in Haskell?
...012 period, the following things have happened:
2012:
From 2012, the parallel Haskell status updates began appearing in the Parallel Haskell Digest.
2011:
Parallel and Concurrent Programming in Haskell, a tutorial. version 1.1 released by Simon Marlow
Haskell and parallelism, mentioned in an ...
What is javax.inject.Named annotation supposed to be used for?
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So @Named really is @Qualifier, so why is @Qualifier required to be so generic, is the idea to allow someone using javax.inject to define stereotypes like @Repository,@Service,@Controller that are marked up as @Qualifier?
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Java packages com and org
...ode Conventions:
The prefix of a unique package name is always written in all-lowercase ASCII letters and should be one of the top-level domain names, currently com, edu, gov, mil, net, org, or one of the English two-letter codes identifying countries as specified in ISO Standard 3166, 1981.
Subseq...