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What's the difference between the atomic and nonatomic attributes?
...o are identical; "atomic" is the default behavior (note that it is not actually a keyword; it is specified only by the absence of nonatomic -- atomic was added as a keyword in recent versions of llvm/clang).
Assuming that you are @synthesizing the method implementations, atomic vs. non-atomic chang...
Longest line in a file
...ing for a simple way to find the length of the longest line in a file. Ideally, it would be a simple bash shell command instead of a script.
...
How to enumerate an enum with String type?
...h Xcode 10), just add protocol conformance to CaseIterable to benefit from allCases. To add this protocol conformance, you simply need to write somewhere:
extension Suit: CaseIterable {}
If the enum is your own, you may specify the conformance directly in the declaration:
enum Suit: String, CaseIte...
How do I select a random value from an enumeration?
...
Use Enum.GetValues to retrieve an array of all values. Then select a random array item.
static Random _R = new Random ();
static T RandomEnumValue<T> ()
{
var v = Enum.GetValues (typeof (T));
return (T) v.GetValue (_R.Next(v.Length));
}
Test:
for (in...
How do you manage databases in development, test, and production?
...of good options. I wouldn't use the "restore a backup" strategy.
Script all your schema changes, and have your CI server run those scripts on the database. Have a version table to keep track of the current database version, and only execute the scripts if they are for a newer version.
Use a migr...
How to add a 'or' condition in #ifdef
...¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|//
#ifdef CONDITION_01 //| |//
#define TEMP_MACRO //| |//
#endif //| |//
#ifdef CONDITION_02 //| |//
#define TEMP_MACRO //| |//
#endif ...
Best practice multi language website
...ome months now, but I haven't been in a situation that I needed to explore all possible options before. Right now, I feel like it's time to get to know the possibilities and create my own personal preference to use in my upcoming projects.
...
What's the difference between globals(), locals(), and vars()?
... the same dict each time - it's attached to the stack frame object as its f_locals attribute. The dict's contents are updated on each locals() call and each f_locals attribute access, but only on such calls or attribute accesses. It does not automatically update when variables are assigned, and assi...
Apply .gitignore on an existing repository already tracking large number of files
...
This answer solved my problem:
First of all, commit all pending changes.
Then run this command:
git rm -r --cached .
This removes everything from the index, then just run:
git add .
Commit it:
git commit -m ".gitignore is now working"
...
Saving images in Python at a very high quality
...nd trying to get good figures in a latex document, save as an eps. Specifically, try something like this after running the commands to plot the image:
plt.savefig('destination_path.eps', format='eps')
I have found that eps files work best and the dpi parameter is what really makes them look good ...