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Best explanation for languages without null
... that every reference type gets this extra state in its space that is typically undesired. A string variable could be any sequence of characters, or it could be this crazy extra null value that doesn't map into my problem domain. A Triangle object has three Points, which themselves have X and Y va...
Suppressing deprecated warnings in Xcode
With all the SDKs floating around, it's handy to be able to build for multiple SDKs and platforms. However, bouncing from 3.2 to 3.0 and even occasionally 2.x, I frequently get deprecated warnings involving methods that have changed or been superseded:
...
Extracting bits with a single multiplication
.....
A multiplication is a bunch of shift-and-add operations. The key is to allow overflow to "shift away" the bits we don't need and put the ones we want in the right place.
Multiplication by 4 (00000100) would shift everything left by 2 and get you to a00b0000 . To get the b to move up we need to...
Linux - Replacing spaces in the file names
...umber of files in a folder, and I want to replace every space character in all file names with underscores. How can I achieve this?
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How to add a progress bar to a shell script?
...}
done
If you already have a loop which does a lot of work, you can call the
following function at the beginning of each iteration to update the
spinner:
sp="/-\|"
sc=0
spin() {
printf "\b${sp:sc++:1}"
((sc==${#sp})) && sc=0
}
endspin() {
printf "\r%s\n" "$@"
}
until wor...
How to customize the background/border colors of a grouped table view cell?
...later UITableViewCell now has a backgroundColor property that makes this really easy (especially in combination with the [UIColor colorWithPatternImage:] initializer). But I'll leave the 2.0 version of the answer here for anyone that needs it…
It's harder than it really should be. Here's how I ...
C# operator overload for `+=`?
...nguage has its own operators list, which are compiled in a special method calls, and CLR itself doesn't know anything about operators. So let's see what exactly stays behind the + and += operators.
See this simple code:
Decimal d = 10M;
d = d + 10M;
Console.WriteLine(d);
Let view the IL-code for...
Quick easy way to migrate SQLite3 to MySQL? [closed]
...y's built a solid library that can convert between the two.
Here a list of ALL the differences in SQL syntax that I know about between the two file formats:
The lines starting with:
BEGIN TRANSACTION
COMMIT
sqlite_sequence
CREATE UNIQUE INDEX
are not used in MySQL
SQLite uses CREATE TABLE/INSERT ...
Python threading.timer - repeat function every 'n' seconds
... not self.stopped.wait(0.5):
print("my thread")
# call a function
In the code that started the timer, you can then set the stopped event to stop the timer.
stopFlag = Event()
thread = MyThread(stopFlag)
thread.start()
# this will stop the timer
stopFlag.set()
...
Fixed size queue which automatically dequeues old values upon new enques
...ur own queue, just use the inherited one. If you do as you do, you can actually do nothing else with the queue values, all other functions but your new Enqueue will still call the original queue. In other words, although this answer is marked as accepted, it's completely and utterly broken.
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