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Placeholder in UITextView

...uble. UIPlaceHolderTextView.h: #import <Foundation/Foundation.h> IB_DESIGNABLE @interface UIPlaceHolderTextView : UITextView @property (nonatomic, retain) IBInspectable NSString *placeholder; @property (nonatomic, retain) IBInspectable UIColor *placeholderColor; -(void)textChanged:(NSNotif...
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Why do we need virtual functions in C++?

...s to more general). Visa-versa you need an explicit cast, usually a dynamic_cast. Anything else - very prone to undefined behavior so make sure you know what you're doing. To the best of my knowledge, this has not changed since before even C++98. – Steve314 Jun...
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Convert PDF to clean SVG? [closed]

...andy guide on how to do so! http://en.wikipedia.org/wiki/Wikipedia:Graphic_Lab/Resources/PDF_conversion_to_SVG#Conversion_with_Inkscape share | improve this answer | follow ...
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What is the difference between require_relative and require in Ruby?

What is the difference between require_relative and require in Ruby? 7 Answers 7 ...
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Declare and initialize a Dictionary in Typescript

... Edit: This has since been fixed in the latest TS versions. Quoting @Simon_Weaver's comment on the OP's post: Note: this has since been fixed (not sure which exact TS version). I get these errors in VS, as you would expect: Index signatures are incompatible. Type '{ firstName: string; }' is...
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What is __gxx_personality_v0 for?

... quick grep of the libstd++ code base revealed the following two usages of __gx_personality_v0: In libsupc++/unwind-cxx.h // GNU C++ personality routine, Version 0. extern "C" _Unwind_Reason_Code __gxx_personality_v0 (int, _Unwind_Action, _Unwind_Exceptio...
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Is there any difference between “foo is None” and “foo == None”?

...pares the same object instance Whereas == is ultimately determined by the __eq__() method i.e. >>> class Foo(object): def __eq__(self, other): return True >>> f = Foo() >>> f == None True >>> f is None False ...
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How do I check if an object has a specific property in JavaScript?

...2: " + prop ); } function hasOwnProperty(obj, prop) { var proto = obj.__proto__ || obj.constructor.prototype; return (prop in obj) && (!(prop in proto) || proto[prop] !== obj[prop]); } if ( Object.prototype.hasOwnProperty ) { var hasOwnProperty = function(obj, prop) { ...
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Good example of livelock?

...deadlocks. This the output from console; 2016-09-12 21:31:45.065 :: [Maker_0:WAITING, Maker_1:WAITING, Maker_2:WAITING, Maker_3:WAITING, Maker_4:WAITING, Maker_5:WAITING, Maker_6:WAITING, Maker_7:WAITING, pool-7-thread-1:TIMED_WAITING, pool-7-thread-2:TIMED_WAITING, pool-8-thread-1:TIMED_WAITING, p...
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How to avoid circular imports in Python? [duplicate]

... Doesn't seem to work with submodules import foobar.mod_a and import foobar.mod_b doesn't work like described above. – Nick Oct 2 '13 at 0:39 ...