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What is the difference between Scala's case class and class?
...xclusively depend on their constructor arguments.
This functional concept allows us to
use a compact initialization syntax (Node(1, Leaf(2), None)))
decompose them using pattern matching
have equality comparisons implicitly defined
In combination with inheritance, case classes are used to mimi...
MySQL CONCAT returns NULL if any field contain NULL
...es: it returns the first non-NULL value parameter passed to it (or NULL if all parameters are NULL). By passing an empty string as the second parameter, you are guaranteeing it will not return NULL.
– Jo.
Mar 10 '17 at 17:03
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What does enctype='multipart/form-data' mean?
...of the URL.
multipart/form-data is significantly more complicated but it allows entire files to be included in the data. An example of the result can be found in the HTML 4 specification.
text/plain is introduced by HTML 5 and is useful only for debugging — from the spec: They are not reliably...
In c++ what does a tilde “~” before a function name signify?
... memory, etc. etc.
Here's a description from ibm.com:
Destructors are usually used to deallocate memory and do other cleanup for a class object and its class members when the object is destroyed. A destructor is called for a class object when that object passes out of scope or is explicitly delete...
What does template mean?
...
template<void (*F)()>
struct FunctionWrapper {
static void call_it() { F(); }
};
// pass address of function do_it as argument.
void do_it() { }
FunctionWrapper<&do_it> test;
Template reference parameter (passing an integer)
template<int &A>
struct SillyExample {
...
Percentage Height HTML 5/CSS
...’, which is the nearest ancestor to also be positioned.)
Alternatively, all modern browsers and IE>=9 support new CSS units relative to viewport height (vh) and viewport width (vw):
div {
height:100vh;
}
See here for more info.
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mysql check collation of a table
...
The above answer is great, but it doesn't actually provide an example that saves the user from having to look up the syntax:
show table status like 'test';
Where test is the table name.
(Corrected as per comments below.)
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Where is the “Fold” LINQ Extension Method?
I found in MSDN's Linq samples a neat method called Fold() that I want to use. Their example:
2 Answers
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Git interactive rebase no commits to pick
... pushed
for your second question: have a branch with your changes (basically a configuration branch) and regularly merge the other branches into it. this way the changes will not move to other branches
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JS: Check if date is less than 1 hour ago?
...terchange, yes. If n hours ago is the same as -n hours in the future, then all future dates are less than one hour ago.
– Mike Samuel
Nov 20 '18 at 0:03
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