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What's the cleanest way of applying map() to a dictionary in Swift?
...
Swift 4+
Good news! Swift 4 includes a mapValues(_:) method which constructs a copy of a dictionary with the same keys, but different values. It also includes a filter(_:) overload which returns a Dictionary, and init(uniqueKeysWithValues:) and init(_:uniquingKeysWith:) ini...
How to replace spaces in file names using a bash script
...ystem already. Do it in two steps:
find -name "* *" -type d | rename 's/ /_/g' # do the directories first
find -name "* *" -type f | rename 's/ /_/g'
Based on Jürgen's answer and able to handle multiple layers of files and directories in a single bound using the "Revision 1.5 1998/12/18 16:1...
Can comments be used in JSON?
...hen it will be data too.
You could have a designated data element called "_comment" (or something) that would be ignored by apps that use the JSON data.
You would probably be better having the comment in the processes that generates/receives the JSON, as they are supposed to know what the JSON dat...
Objective-C : BOOL vs bool
...
From the definition in objc.h:
#if (TARGET_OS_IPHONE && __LP64__) || TARGET_OS_WATCH
typedef bool BOOL;
#else
typedef signed char BOOL;
// BOOL is explicitly signed so @encode(BOOL) == "c" rather than "C"
// even if -funsigned-char is used.
#endif
#defin...
How to write the Fibonacci Sequence?
... now be 1, and b will also be 1, (0 + 1)
and usage:
for index, fibonacci_number in zip(range(10), fib()):
print('{i:3}: {f:3}'.format(i=index, f=fibonacci_number))
prints:
0: 0
1: 1
2: 1
3: 2
4: 3
5: 5
6: 8
7: 13
8: 21
9: 34
10: 55
(For attribution...
What's the $unwind operator in MongoDB?
...owing documents:
{
"result" : [
{
"_id" : ObjectId("4e6e4ef557b77501a49233f6"),
"title" : "this is my title",
"author" : "bob",
"tags" : "fun"
},
{
"_...
UTF-8: General? Bin? Unicode?
...
In general, utf8_general_ci is faster than utf8_unicode_ci, but less correct.
Here is the difference:
For any Unicode character set, operations performed using the _general_ci collation are faster than those for the _unicode_ci collatio...
Fixed size queue which automatically dequeues old values upon new enques
...T> : IReadOnlyCollection<T>
{
private readonly Queue<T> _queue = new Queue<T>();
private readonly object _lock = new object();
public int Count { get { lock (_lock) { return _queue.Count; } } }
public int Limit { get; }
public FixedSizedQueue(int limit)
...
What's the deal with a leading underscore in PHP class methods?
...private with an underscore. In some older classes you'll see /**private*/ __foo() { to give it some extra weight.
I've never heard of developers prefacing all their methods with underscores, so I can't begin to explain what causes that.
...
Which is better in python, del or delattr?
.... del foo.bar compiles to two bytecode instructions:
2 0 LOAD_FAST 0 (foo)
3 DELETE_ATTR 0 (bar)
whereas delattr(foo, "bar") takes five:
2 0 LOAD_GLOBAL 0 (delattr)
3 LOAD_FAST 0 (foo)
...