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Can not connect to local PostgreSQL
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This really looks like a file permissions error. Unix domain sockets are files and have user permissions just like any other. It looks as though the OSX user attempting to access the database does not have file permissions to acce...
Signed to unsigned conversion in C - is it always safe?
...herwise, if the type of the operand with signed integer type can represent all of the values of the type of the operand with unsigned integer type, then the operand with unsigned integer type is converted to the type of the operand with signed integer type.
Otherwise, both operands are converted t...
How to copy from current position to the end of line in vi
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If you don't want to include the line break with the yank, you can use yg_. (Or in your case, "*yg_)
Basically, just recognize there's a difference between $ and g_ movement-wise. It's helped me on numerous occasions.
sha...
How to format a java.sql Timestamp for displaying?
...SQL and want the database itself to perform the conversion, use this:
DATE_FORMAT(date,format)
If you prefer to format using Java, use this:
java.text.SimpleDateFormat
SimpleDateFormat dateFormat = new SimpleDateFormat("M/dd/yyyy");
dateFormat.format( new Date() );
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What is “lifting” in Scala?
...ethod into a function by applying the underscore
scala> val f = times2 _
f: Int => Int = <function1>
scala> f(4)
res0: Int = 8
Note the fundamental difference between methods and functions. res0 is an instance (i.e. it is a value) of the (function) type (Int => Int)
Functors
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How can I reliably get an object's address when operator& is overloaded?
...argument and returning no result. This reference to a function can be trivially converted into a pointer to function -- from @Konstantin: According to 13.3.3.2 both T & and T * are indistinguishable for functions. The 1st one is an Identity conversion and the 2nd one is Function-to-Pointer conve...
How do I set bold and italic on UILabel of iPhone/iPad?
...t {
return with([.traitBold, .traitItalic])
}
func with(_ traits: UIFontDescriptor.SymbolicTraits...) -> UIFont {
guard let descriptor = self.fontDescriptor.withSymbolicTraits(UIFontDescriptor.SymbolicTraits(traits).union(self.fontDescriptor.symbolicTraits)) else {
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Centering a background image, using CSS
...nd-image:url(https://upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Dore_woodcut_Divine_Comedy_01.jpg/481px-Dore_woodcut_Divine_Comedy_01.jpg);
background-repeat:no-repeat;
background-position: center;
background-size: cover;
html{
height:100%
}
body{
background-image:url(https://uplo...
Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...
How do I allow HTTPS for Apache on localhost?
... up HTTPS with a self-signed cert on Apache on localhost, but how do I actually do that? I have no idea at all.
16 Answers
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