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Proper use of beginBackgroundTaskWithExpirationHandler

I'm a bit confused about how and when to use beginBackgroundTaskWithExpirationHandler . 5 Answers ...
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How to read if a checkbox is checked in PHP?

...s: <input type="checkbox" name="test" value="value1"> After submitting the form you can check it with: isset($_POST['test']) or if ($_POST['test'] == 'value1') ... share | improv...
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Is there a way to instantiate objects from a string holding their class name?

...static Base * createInstance(std::string const& s) { map_type::iterator it = getMap()->find(s); if(it == getMap()->end()) return 0; return it->second(); } protected: static map_type * getMap() { // never delete'ed. (exist until progra...
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How do I get a list of column names from a psycopg2 cursor?

... "Programming Python" by Mark Lutz: curs.execute("Select * FROM people LIMIT 0") colnames = [desc[0] for desc in curs.description] share | improve this answer | follow ...
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In Flux architecture, how do you manage Store lifecycle?

...data flows through this central hub. Having a singleton Dispatcher allows it to manage all Stores. This becomes important when you need Store #1 update itself, and then have Store #2 update itself based on both the Action and on the state of Store #1. Flux assumes this situation is an eventuality...
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Javascript replace with reference to matched group?

... string, such as hello _there_ . I'd like to replace the two underscores with <div> and </div> respectively, using JavaScript . The output would (therefore) look like hello <div>there</div> . The string might contain multiple pairs of underscores. ...
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Avoid duplicates in INSERT INTO SELECT query in SQL Server

...follow | edited Jan 29 '19 at 2:07 nloewen 1,1731010 silver badges1818 bronze badges answ...
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Structure padding and packing

...daries - say, int members would have offsets, which are mod(4) == 0 on 32-bit platform. Padding is on by default. It inserts the following "gaps" into your first structure: struct mystruct_A { char a; char gap_0[3]; /* inserted by compiler: for alignment of b */ int b; char c; c...
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MongoDB: Combine data from multiple collections into one..how?

...s.country, gender: this.gender, age: this.age }; emit(this._id, values); }; mapComments = function() { var values = { commentId: this._id, comment: this.comment, created: this.created }; emit(this.userId, values); }; reduce = function(k, va...
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Kotlin secondary constructor

...tring? = null) {...} usage: val c1 = C("foo") // parameter passed explicitly val c2 = C() // default value used Note that default values work for any function, not only for constructors Technique 3. (when you need encapsulation) Use a factory method defined in a companion object Sometimes you...