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Are nullable types reference types?
...Guide):
Nullable types are instances of the System.Nullable struct.
and
Nullable types represent value-type variables that can be assigned the value of null. You cannot create a nullable type based on a reference type. (Reference types already support the null value.)
So, no they're not...
Java: int array initializes with nonzero elements
... with a situation where it is not. Such a behavior occurs first in JDK 7u4 and also occurs in all later updates (I use 64-bit implementation). The following code throws exception:
...
How do you run a single query through mysql from the command line?
...hould be the first result in a google search (for "mysql exec sql from command line") and not the huge mysql site!
– Guillaume Bois
Apr 4 '17 at 17:48
4
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Add hover text without javascript like we hover on a user's reputation
...over on a user's reputation we see a text. I have seen this at many places and the source code tells me that it can be done without js. And i tried and got only this-
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Sass .scss: Nesting and multiple classes?
...ng the &.
This notation is most often used to write pseudo-elements and -classes:
.element{
&:hover{ ... }
&:nth-child(1){ ... }
}
However, you can place the & at virtually any position you like*, so the following is possible too:
.container {
background:red;
#...
jQuery exclude elements with certain class in selector
...e two approaches, except .not() is more readable (especially when chained) and :not() is very marginally faster. See this Stack Overflow answer for more info on the differences.
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validation custom message for rails 3
... edited Mar 4 '15 at 3:20
Andrew Hendrie
5,08722 gold badges3434 silver badges6262 bronze badges
answered Mar 22 '11 at 4:33
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Twig ternary operator, Shorthand if-then-else
Does Twig support ternary (shorthand if-else) operator?
3 Answers
3
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Git: updating remote branch information
...r remote_name/branch_name
you only remove your local checkout. This command doesn't do anything to the remote repository, which is why it still shows up.
Solution:
git push origin :branch_name
will remove the the remote branch (note the ':'), and
git branch -d branch_name
will remove your ...
What does SQL clause “GROUP BY 1” mean?
...t_id.
You also can specify in ORDER BY.
Note : The number in ORDER BY and GROUP BY always start with 1 not with 0.
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