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Difference between Covariance & Contra-variance
...ng function that associates one member of a set with another. More specifically, a mapping can be covariant or contravariant with respect to a relation on that set.
Consider the following two subsets of the set of all C# types. First:
{ Animal,
Tiger,
Fruit,
Banana }.
And second, this c...
advantage of tap method in ruby
...= User.new
user.username = "foobar"
user.save!
they would have to follow all the three lines and then recognize that it is just creating an instance named user.
If it were:
user = User.new.tap do |u|
u.username = "foobar"
u.save!
end
then that would be immediately clear. A reader would not...
get the latest fragment in backstack
...gment in the back stack twice, you can't retrieve a specific fragment when all you have is the index or backstackentry entity.
– Justin
May 29 '14 at 15:54
14
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How to pad zeroes to a string?
...ited in the parens; since only one thing is being printed, it works identically now on Py2 and Py3.
– ShadowRanger
Jan 25 '19 at 2:19
2
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Get first and last date of current month with JavaScript or jQuery [duplicate]
...+1" and day "0" of the month to get the last day of the previous month, it all works per the spec; see developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/…
– Ed Staub
Oct 24 '15 at 3:31
...
Visual Studio retrieving an incorrect path to a project from somewhere
...
.suo file is hidden so you need to enable "show all files and folder" option
– ANIL MANE
Feb 26 '15 at 16:54
8
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Why does sizeof(x++) not increment x?
..., in particular this would mean that in something like sizeof(int[++x]) (really, really a bad idea, anyhow) the ++ could be evaluated.
– Jens Gustedt
Nov 22 '11 at 12:01
3
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Declaring pointers; asterisk on the left or right of the space between the type and name? [duplicate
...r;
is emphasizing the type of the pointer variable. It is saying, essentially, "the type of somePtr is pointer-to-someType".
The style
someType *somePtr
is emphasizing the type of the pointed-to data. It is saying, essentially, "the type of data pointed to by somePtr is someType".
They both m...
What is the difference between Trap and Interrupt?
...mory access. It's also the usual way to invoke a kernel routine (a system call) because those run with a higher priority than user code. Handling is synchronous (so the user code is suspended and continues afterwards). In a sense they are "active" - most of the time, the code expects the trap to hap...
What does the ng stand for in Angular.js directives
...
The prefix ng stands for "Angular;" all of the built-in directives that ship with Angular use that prefix. Similarly, it is recommended that you do not use the ng prefix on your own directives in order to avoid possible name collisions in future versions of Ang...