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Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
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The reason for first one working:
From MSDN:
In string concatenation operations,the C# compiler treats a null string the same as an empty string, but it does not convert the value of the original null string.
More information on the + binary operator:...
How to pattern match using regular expression in Scala?
I would like to be able to find a match between the first letter of a word, and one of the letters in a group such as "ABC". In pseudocode, this might look something like:
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Adding a directory to the PATH environment variable in Windows
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Peter Mortensen
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answered Mar 3 '12 at 13:23
Hans PassantHans ...
NoClassDefFoundError: android.support.v7.internal.view.menu.MenuBuilder
...the Android appcompat v7 library on Samsung devices running Android 4.2. I keep getting crashes with the following stack trace in my Developer Console:
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What does the exclamation mark do before the function?
...run the function.
Now, when we add the seemingly innocuous exclamation mark: !function foo() {} it turns it into an expression. It is now a function expression.
The ! alone doesn't invoke the function, of course, but we can now put () at the end: !function foo() {}() which has higher precedence th...
What is the purpose of base 64 encoding and why it used in HTTP Basic Authentication?
...ata using only printable (text) characters.
See this paragraph from the wikipedia page for HTTP Basic Authentication:
While encoding the user name and password with the Base64 algorithm typically makes them unreadable by the naked eye, they are as easily decoded as they are encoded. Security is...
entity object cannot be referenced by multiple instances of IEntityChangeTracker. while adding relat
...y contact, which is validated I get the exception "ADO.Net Entity Framework An entity object cannot be referenced by multiple instances of IEntityChangeTracker"
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Calculate MD5 checksum for a file
...fied. If the text and modification date cannot be obtained, is a MD5 checksum the most reliable way to tell if the file has changed?
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How to unsubscribe to a broadcast event in angularJS. How to remove function registered via $on
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fracz
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answered Feb 15 '13 at 16:16
Liviu T.Liviu T....
How do I discover memory usage of my application in Android?
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Note that memory usage on modern operating systems like Linux is an extremely complicated and difficult to understand area. In fact the chances of you actually correctly interpreting whatever numbers you get is extremely low. (Pretty much every time I look at memory usage num...