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What's the false operator in C# good for?
...itly.
Comparing to SQL, imagine a table Table with 3 rows with value Foo set to true, 3 rows with value Foo set to false and 3 rows with value Foo set to null.
SELECT COUNT(*) FROM Table WHERE Foo = TRUE OR Foo = FALSE
6
In order to count all rows you'd have to do the following:-
SELECT COUNT(...
What do (lambda) function closures capture?
...recommended by Adrien Plisson. Create a lambda with an extra argument, and set the extra argument's default value to the object you want preserved.
A little more verbose but less hacky would be to create a new scope each time you create the lambda:
>>> adders = [0,1,2,3]
>>> for i...
Why use Abstract Base Classes in Python?
... much value by itself, I agree. I suspect it was added to allow (for e.g.) Set to inherit from it. By the time you get to Set, suddenly belonging to the the ABC has considerable semantics. An item can't belong to the collection twice. That is NOT detectable by the existence of methods.
...
How do I get the real .height() of a overflow: hidden or overflow: scroll div?
...height of the collapsed DIV but after that, it's all CSS.
1) Fetching and setting height
Fetch the inner height of the collapsed element (using scrollHeight). My element has a class .section__accordeon__content and I actually run this in a forEach() loop to set the height for all panels, but you g...
How to prevent vim from creating (and leaving) temporary files?
... recommend to keep working with swap files (in case Vim crashes).
You can set the directory where the swap files are stored, so they don't clutter your normal directories:
set swapfile
set dir=~/tmp
See also
:help swap-file
...
How can I save an image to the camera roll?
...save an image to the device's camera roll. All that I have done so far is set up an IBAction for the button to save the image. What library method or function can I use to save an image to the user's camera roll?
...
What does “Mass Assignment” mean in Laravel?
...Mass assignment is when you send an array to the model creation, basically setting a bunch of fields on the model in a single go, rather than one by one, something like:
$user = new User(request()->all());
(This is instead of explicitly setting each value on the model separately.)
You can us...
What is the difference between \r and \n?
...dardized on NL--a character that doesn't even exist in the ASCII character set. In Unicode, NL is U+0085 NEXT LINE, but the actual EBCDIC value is 0x15.
Why did different systems choose different methods? Simply because there was no universal standard. Where your keyboard probably says "Enter",...
Why is rbindlist “better” than rbind?
...s of memory rbindlist is implemented in C, so is memory efficient, it uses setattr to set attributes by reference
rbind.data.frame is implemented in R, it does lots of assigning, and uses attr<- (and class<- and rownames<- all of which will (internally) create copies of the created data.fr...
Is it safe to use -1 to set all bits to true?
...its one (it has, of course)." -- whaat??? I thought the whole point was to set all bits to 1. That's how flags work..no?? You look at the bits. Who cares about the value?
– mpen
Aug 1 '10 at 21:11
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