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NSDate beginning of day and end of day
...n)!
let specificDate = Date("2020-01-01")
extension Date {
init(_ dateString:String) {
let dateStringFormatter = DateFormatter()
dateStringFormatter.dateFormat = "yyyy-MM-dd"
dateStringFormatter.locale = NSLocale(localeIdentifier: "en_US_POSIX") as Locale
let dat...
When to add what indexes in a table in Rails
...add:
add_index :photos, [:created_at, :version]
Note:
An index takes up extra space on the disk and makes it slower to create and update each record, because it has to rebuild each index.
Credit:
https://tomafro.net/2009/08/using-indexes-in-rails-choosing-additional-indexes, rails - created_at ...
Given the lat/long coordinates, how can we find out the city/country?
...okups per second)
Disadvantages:
Not automatically up to date
Requires extra code if you want to distinguish the case where the nearest city is dozens of miles away
May give weird results near the poles and the international date line (though there aren't any cities in those places anyway
...
Renaming a branch while on pull request
...uild system work, and also not lose any information (although there was an extra step in tracking it).
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YAML current date in rmarkdown
... a list includes: after_body: [ ... ] as valid YAML would only be filename strings... So no possibility of includes: "`r list.files(...)`" ?
– Louis Maddox
Mar 2 '15 at 18:33
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Custom attributes - Yea or nay?
...om attributes in their HTML tags, mainly for the purpose of embedding some extra bits of data for use in javascript code.
1...
How do I install a custom font on an HTML site
... answered Dec 27 '17 at 23:56
Richard StitzRichard Stitz
6111 silver badge44 bronze badges
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Just what is an IntPtr exactly?
...oints to.
In other words, an IntPtr is just like a void* -- but with the extra feature that it can (but shouldn't) be used for basic pointer arithmetic.
In order to dereference an IntPtr, you can either cast it to a true pointer (an operation which can only be performed in "unsafe" contexts) or y...
Loop code for each file in a directory [duplicate]
...returns the type of the file. Thereby possible results would be file, dir, char, block, .... You can use something like mime_content_type() if you want to know the content type of the file.
– vallentin
Jul 24 '15 at 9:08
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Sorting a vector of custom objects
...
A simple example using std::sort
struct MyStruct
{
int key;
std::string stringValue;
MyStruct(int k, const std::string& s) : key(k), stringValue(s) {}
};
struct less_than_key
{
inline bool operator() (const MyStruct& struct1, const MyStruct& struct2)
{
ret...