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How to encode a URL in Swift [duplicate]
...
Swift 4.2
var urlString = originalString.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)
Swift 3.0
var address = "American Tourister, Abids Road, Bogulkunta, Hyderabad, Andhra Pradesh, India"
let escapedAddress = address.addingPercentEncoding(withAllowedCharacters: Characte...
What is the “FS”/“GS” register intended for?
...dows and Linux.
The original intention behind the segment registers was to allow a program to access many different (large) segments of memory that were intended to be independent and part of a persistent virtual store. The idea was taken from the 1966 Multics operating system, that treated files a...
Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by:
5 Answers
...
Caching a jquery ajax response in javascript/browser
... return localCache.data[url];
},
set: function (url, cachedData, callback) {
localCache.remove(url);
localCache.data[url] = cachedData;
if ($.isFunction(callback)) callback(cachedData);
}
};
$(function () {
var url = '/echo/jsonp/';
$('#ajaxButton').clic...
Transaction isolation levels relation with locks on table
...B just executes a SELECT statement to read data. C reads and updates data. All these process work on the same table T.
READ UNCOMMITTED - no lock on the table. You can read data in the table while writing on it. This means A writes data (uncommitted) and B can read this uncommitted data and use it...
Image comparison - fast algorithm
...ow.
The second method uses only elementary image processing, and is potentially faster than the first approach, and is straightforward to implement. However, what it gains in understandability, it lacks in robustness -- matching fails on scaled, rotated, or discolored images.
The third method is bo...
iPhone UITextField - Change placeholder text color
...olor blackColor];
textField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:placeholderText attributes:@{NSForegroundColorAttributeName: color}];
} else {
NSLog(@"Cannot set placeholder text's color, because deployment target is earlier than iOS 6.0");
// TODO: Add fall-back...
ALTER TABLE to add a composite primary key
I have a table called provider . I have three columns called person , place , thing . There can be duplicate persons, duplicate places, and duplicate things, but there can never be a dupicate person-place-thing combination.
...
Can't find the PostgreSQL client library (libpq)
...
$ sudo su
$ env ARCHFLAGS="-arch x86_64" gem install pg
Building native extensions. This could take a while...
Successfully installed pg-0.11.0
1 gem installed
Installing ri documentation for pg-0.11.0...
Installing RDoc documentation for pg-0.11.0...
WORKE...
Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
...0 +0000" GIT_COMMITTER_DATE="Thu, 01 Jan 1970 00:00:00 +0000" git commit --allow-empty -m 'Initial commit'
Will give you:
(See the tree SHA1?)
You can even rebase your existing history on top of that empty commit (see "git: how to insert a commit as the first, shifting all the others?")
In bo...