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How to trim a string to N chars in Javascript?

How can I, using Javascript, make a function that will trim string passed as argument, to a specified length, also passed as argument. For example: ...
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Is it better in C++ to pass by value or pass by constant reference?

...or large objects that implement proper move constructors (such as vectors, strings …), the second case is then vastly more efficient than the first. Therefore, it is recommended to use pass by value if the function takes ownership of the argument, and if the object type supports efficient moving. ...
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How can I use map and receive an index as well in Scala?

...ted scala> ci map (i => i+"=#"+ci.count) toList res0: List[java.lang.String] = List(These=#0,are=#1,words=#2) share | improve this answer | follow | ...
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How do I do base64 encoding on iOS?

...or Objective C categories. For Base64 encoding: #import <Foundation/NSString.h> @interface NSString (NSStringAdditions) + (NSString *) base64StringFromData:(NSData *)data length:(int)length; @end ------------------------------------------- #import "NSStringAdditions.h" static char base...
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How to define a preprocessor symbol in Xcode

... As an addendum, if you are using this technique to define strings in your target, this is how I had to define and use them: In Build Settings -> Preprocessor Macros, and yes backslashes are critical in the definition: APPURL_NSString=\@\"www.foobar.org\" And in the source cod...
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What is the purpose of std::make_pair vs the constructor of std::pair?

... int main() { MyClass<int> my_class(1); } then: g++-8 -Wall -Wextra -Wpedantic -std=c++17 main.cpp compiles happily, but: g++-8 -Wall -Wextra -Wpedantic -std=c++14 main.cpp fails with: main.cpp: In function ‘int main()’: main.cpp:13:13: error: missing template arguments before...
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Sanitizing strings to make them URL and filename safe?

...ying to come up with a function that does a good job of sanitizing certain strings so that they are safe to use in the URL (like a post slug) and also safe to use as file names. For example, when someone uploads a file I want to make sure that I remove all dangerous characters from the name. ...
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In STL maps, is it better to use map::insert than []?

...y create: using std::cout; using std::endl; typedef std::map<int, std::string> MyMap; MyMap map; // ... std::pair<MyMap::iterator, bool> res = map.insert(MyMap::value_type(key,value)); if ( ! res.second ) { cout << "key " << key << " already exists " <...
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Fastest way to flatten / un-flatten nested JSON objects

...d more speed out of your implementation by replacing the regex.exec() with string.split() and simplifying the key format. I'll give it a few days before I award you the pts, but I think the 'wall of meaningful optimization' has been reached. – Louis Ricci Oct 5...
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What is the use of the %n format specifier in C?

... Oh my - this is a character-based version of computing the pixel size of string in a given font! – user3458 Aug 4 '10 at 12:41 ...