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What is the relative performance difference of if/else versus switch statement in Java?
...ic interface Action {
void execute(String input);
}
And get hold of all implementations in some Map. You can do this either statically or dynamically:
Map<String, Action> actions = new HashMap<String, Action>();
Finally replace the if/else or switch by something like this (leav...
What is the difference between Python's list methods append and extend?
...
Actually there's a big difference - x + [4, 5] gives you a new list assigned to x - x.extend() mutates the original list. I elaborate in my answer here below.
– Aaron Hall♦
Jul 17 '17 at 1...
How to find the mysql data directory from command line in windows
In linux I could find the mysql installation directory with the command which mysql . But I could not find any in windows. I tried echo %path% and it resulted many paths along with path to mysql bin.
...
How do I get the row count of a pandas DataFrame?
...[0].count()", "len(data.index)"],
xlabel="data rows"
)
EDIT: As @Dan Allen noted in the comments len(df.index) and df[0].count() are not interchangeable as count excludes NaNs,
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How to create NS_OPTIONS-style bitmask enumerations in Swift?
...tains(.secondOption) {
print("multipleOptions has SecondOption")
}
let allOptions = MyOptions(rawValue: 7)
if allOptions.contains(.thirdOption) {
print("allOptions has ThirdOption")
}
Swift 2.0
In Swift 2.0, protocol extensions take care of most of the boilerplate for these, which are now...
Better way to check variable for null or empty string?
...solves it, I'm not sure if it's simpler. +1 anyway
– Allain Lalonde
Dec 19 '08 at 15:36
4
Since O...
Example of multipart/form-data
...6 is two hyphens shorter then the actual boundaries in the data. This is really, really hard to see with all the hyphens strung together.
– Fake Name
Jun 2 '17 at 6:39
...
Get the current first responder without using a private API
...that my app cannot be accepted because I'm using a non-public API; specifically, it says,
28 Answers
...
Convert hex string to int in Python
... 16)
With the 0x prefix, Python can distinguish hex and decimal automatically.
>>> print int("0xdeadbeef", 0)
3735928559
>>> print int("10", 0)
10
(You must specify 0 as the base in order to invoke this prefix-guessing behavior; omitting the second parameter means to assume ba...
Proper way to handle multiple forms on one page in Django
...ta. Include some hidden inputs if your froms don't have unique fields with all possible values being not empty.
– Denis Otkidach
Oct 24 '09 at 16:39
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