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Best way to convert an ArrayList to a string

...ny fast way to do this? You could loop through it (or remove each element) and concatenate it to a String but I think this will be very slow. ...
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Understanding dispatch_async

...e background. For instance, if I am downloading a file from the internet and I want to update the user on the progress of the download, I will run the download in the priority default queue and update the UI in the main queue asynchronously. dispatch_async(dispatch_get_global_queue( DISPATCH_QUEU...
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What exactly do “u” and “r” string flags do, and what are raw string literals?

...no "escape sequences" to represent newlines, tabs, backspaces, form-feeds, and so on. In normal string literals, each backslash must be doubled up to avoid being taken as the start of an escape sequence. This syntax variant exists mostly because the syntax of regular expression patterns is heavy w...
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HTML5 canvas ctx.fillText won't do line breaks?

...rs in the text you could simulate it by splitting the text at the newlines and calling multiple times the fillText() Something like http://jsfiddle.net/BaG4J/1/ var c = document.getElementById('c').getContext('2d'); c.font = '11px Courier'; console.log(c); var txt = 'line 1\nline 2\nthi...
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Dual emission of constructor symbols

...? This class has no base. Why does it have a "complete object constructor" and a "base object constructor" for each? This Q&A implies to me that this is simply a by-product of polymorphism support, even though it's not actually required in this case. Note that c++filt used to include this info...
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How do I enable EF migrations for multiple contexts to separate databases?

...ecause the Configuration.cs file already exists. If you rename that class and file, you should be able to run that 2nd Enable-Migrations, which will create another Configuration.cs. You will then need to specify which configuration you want to use when updating the databases. Update-Database -Con...
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Cleanest way to write retry logic?

...imply retry the same call can be dangerous if used as a general exception handling mechanism. Having said that, here's a lambda-based retry wrapper that you can use with any method. I chose to factor the number of retries and the retry timeout out as parameters for a bit more flexibility: public st...
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What's the difference between SCSS and Sass?

...een reading, Sass is a language that makes CSS more powerful with variable and math support. 13 Answers ...
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Activity has leaked window that was originally added

What is this error, and why does it happen? 40 Answers 40 ...
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RegEx to extract all matches from string using RegExp.exec

...s an array. For example: const str = 'All of us except @Emran, @Raju and @Noman was there'; console.log( str.match(/@\w*/g) ); // Will log ["@Emran", "@Raju", "@Noman"] share | imp...