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Is there a way to instantiate objects from a string holding their class name?

...ce() { return new T; } typedef std::map<std::string, Base*(*)()> map_type; map_type map; map["DerivedA"] = &createInstance<DerivedA>; map["DerivedB"] = &createInstance<DerivedB>; And then you can do return map[some_string](); Getting a new instance. Another idea is ...
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What's the difference between dynamic (C# 4) and var?

... { [CompilerGenerated] private static class <Main>o__SiteContainer0 { public static CallSite<Action<CallSite, object>> <>p__Site1; } private static void Main(string[] args) { Junk a = new Junk(); /...
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jQuery find events handlers registered with an object

...ta. Read this jQuery blog post. You should now use this instead: jQuery._data( elem, "events" ); elem should be an HTML Element, not a jQuery object, or selector. Please note, that this is an internal, 'private' structure, and shouldn't be modified. Use this for debugging purposes only. In o...
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How to convert DateTime? to DateTime

...this purpose. Using it you end up with this code. DateTime UpdatedTime = _objHotelPackageOrder.UpdatedDate ?? DateTime.Now; share | improve this answer | follow ...
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Why doesn't print work in a lambda?

...ed print function if you are using the latest Python 2.x: In [1324]: from __future__ import print_function In [1325]: f = lambda x: print(x) In [1326]: f("HI") HI share | improve this answer ...
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Convert an image (selected by path) to base64 string

...e to retrieve the base64 string public static string ImageToBase64(string _imagePath) { string _base64String = null; using (System.Drawing.Image _image = System.Drawing.Image.FromFile(_imagePath)) { using (MemoryStream _mStream = new MemoryStream()) ...
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“ImportError: No module named” when trying to run Python script

...d the folder in which you told the notebook to operate from in your ipython_notebook_config.py file (typically using the c.NotebookManager.notebook_dir setting). The solution is to provide the python interpreter with the path-to-your-module. The simplest solution is to append that path to your sys....
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UICollectionView Set number of columns

...orCellWithReuseIdentifier: "Cell") } override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int { return 59 } override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICo...
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Realistic usage of the C99 'restrict' keyword?

...00 00 00 callq 40b <fr+0x1b> 407: R_X86_64_PC32 memset-0x4 40b: 48 83 c4 08 add $0x8,%rsp 40f: 48 89 da mov %rbx,%rdx 412: 48 89 ef mov %rbp,%rdi 415: 5b pop %rbx 416: 5d...
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Does C++ support 'finally' blocks? (And what's this 'RAII' I keep hearing about?)

...ing a mutex: // A class with implements RAII class lock { mutex &m_; public: lock(mutex &m) : m_(m) { m.acquire(); } ~lock() { m_.release(); } }; // A class which uses 'mutex' and 'lock' objects class foo { mutex mutex_; // mutex for l...