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Retain cycle on `self` with blocks

...sue is identical to the workaround for the retain issue; namely, using the __block storage class for the variable. In any case, to answer your question, there's no real alternative here. If you're designing your own block-based API, and it makes sense to do so, you could have the block get passed t...
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How to get the CPU Usage in C#?

...er; cpuCounter = new PerformanceCounter("Processor", "% Processor Time", "_Total"); ramCounter = new PerformanceCounter("Memory", "Available MBytes"); Consume like this: public string getCurrentCpuUsage(){ return cpuCounter.NextValue()+"%"; } public string getAvailableRAM(){ ...
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How do I use Java to read from a file that is actively being written to?

...verflow.com/a/559146/1255493 public void run() { try { while (_running) { Thread.sleep(_updateInterval); long len = _file.length(); if (len < _filePointer) { // Log must have been jibbled or deleted. this.appendMessa...
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Python: try statement in a single line

... I wanted to write up a sequence of actions for debugging: exec "try: some_problematic_thing()\nexcept: problem=sys.exc_info()" print "The problem is %s" % problem[1] For the most part, I'm not at all bothered by the no-single-line-try-except restriction, but when I'm just experimenting and I wan...
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How to determine the Boost version on a system?

... Boost Informational Macros. You need: BOOST_VERSION share | improve this answer | follow | ...
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Read a file in Node.js

... Use path.join(__dirname, '/start.html'); var fs = require('fs'), path = require('path'), filePath = path.join(__dirname, 'start.html'); fs.readFile(filePath, {encoding: 'utf-8'}, function(err,data){ if (!err) { c...
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How do I use IValidatableObject?

... class RangeIfTrueAttribute : RangeAttribute { private readonly string _NameOfBoolProp; public RangeIfTrueAttribute(string nameOfBoolProp, int min, int max) : base(min, max) { _NameOfBoolProp = nameOfBoolProp; } public RangeIfTrueAttribute(string nameOfBoolProp, double ...
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How do you build a Singleton in Dart?

...t's easy to build a singleton: class Singleton { static final Singleton _singleton = Singleton._internal(); factory Singleton() { return _singleton; } Singleton._internal(); } You can construct it like this main() { var s1 = Singleton(); var s2 = Singleton(); print(identical(...
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how to detect search engine bots with php?

... Here's a Search Engine Directory of Spider names Then you use $_SERVER['HTTP_USER_AGENT']; to check if the agent is said spider. if(strstr(strtolower($_SERVER['HTTP_USER_AGENT']), "googlebot")) { // what to do } ...
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I want to get the type of a variable at runtime

...ific type, such as this: val x: Any = 5 def f[T](v: T) = v match { case _: Int => "Int" case _: String => "String" case _ => "Unknown" } f(x) Here it doesn't matter what is the type of the variable, Any. What matters, what is checked is the type of 5, the value. In fact,...