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“is” operator behaves unexpectedly with integers

...tively rare. Here's an example (will work in Python 2 and 3) e.g. SENTINEL_SINGLETON = object() # this will only be created one time. def foo(keyword_argument=None): if keyword_argument is None: print('no argument given to foo') bar() bar(keyword_argument) bar('baz') def b...
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Best practices for in-app database migration for Sqlite

...t/set this variable with the following sqlite statements: > PRAGMA user_version; > PRAGMA user_version = 1; When the app starts, I check the current user-version, apply any changes that are needed to bring the schema up to date, and then update the user-version. I wrap the updates in a t...
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iPhone - Get Position of UIView within entire UIWindow

...ew.frame.origin toView:nil]; 2014 Edit: Looking at the popularity of Matt__C's comment it seems reasonable to point out that the coordinates... don't change when rotating the device. always have their origin in the top left corner of the unrotated screen. are window coordinates: The coordinate s...
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How to call a PHP function on the click of a button

...essfully"); }); }); }); In ajax.php <?php if (isset($_POST['action'])) { switch ($_POST['action']) { case 'insert': insert(); break; case 'select': select(); break; } } ...
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When to use self over $this?

...on-static and static member variables: <?php class X { private $non_static_member = 1; private static $static_member = 2; function __construct() { echo $this->non_static_member . ' ' . self::$static_member; } } new X(); ?> Here is an example of incorr...
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How to find gaps in sequential numbering in mysql?

...rks on table of any size (not just on 100 rows): SELECT (t1.id + 1) as gap_starts_at, (SELECT MIN(t3.id) -1 FROM arrc_vouchers t3 WHERE t3.id > t1.id) as gap_ends_at FROM arrc_vouchers t1 WHERE NOT EXISTS (SELECT t2.id FROM arrc_vouchers t2 WHERE t2.id = t1.id + 1) HAVING gap_ends_at IS ...
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Is gettimeofday() guaranteed to be of microsecond resolution?

...fectively makes the answer to your question no. You should look into clock_gettime(CLOCK_MONOTONIC) for timing intervals. It suffers from several less issues due to things like multi-core systems and external clock settings. Also, look into the clock_getres() function. ...
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AJAX POST and Plus Sign ( + ) — How to Encode?

...a form field via AJAX to a PHP script and using JavaScript to escape(field_contents) . The problem is that any plus signs are being stripped out and replaced by spaces. How can I safely 'encode' the plus sign and then appropriately 'decode' it on the PHP side? ...
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How to suppress scientific notation when printing float values?

...print('{:f}'.format(0.000000123)) 0.000000 – duality_ May 22 '18 at 10:06 1 ...
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Can I use Twitter Bootstrap and jQuery UI at the same time?

...no] - jquery-ui-1.9.2.custom.min.css [images] - ui-bg_diagonals-thick_90_eeeeee_40x40.png - ui-bg_glass_100_e4f1fb_1x400.png - ui-bg_glass_50_3baae3_1x400.png - ui-bg_glass_80_d7ebf9_1x400.png - ui-bg_highlight-hard_100_f2f5f7_1x100.png ...