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How to redirect 404 errors to a page in ExpressJS?

...low, // this means that Express will attempt // to match & call routes _before_ continuing // on, at which point we assume it's a 404 because // no route has handled the request. app.use(app.router); // Since this is the last non-error-handling // middleware use()d, we assume 404, as nothing e...
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Best way to iterate through a Perl array

...C instead of Perl, and no needless copying of the array elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.) #5 might be similar. In terms memory usage: They're all the same except for #5. for (@a) is special-cased to avoid flattening the a...
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Method overloading in Objective-C?

...sign pattern) Here's a simple example on how function overloading works: __attribute__((overloadable)) float area(Circle * this) { return M_PI*this.radius*this.radius; } __attribute__((overloadable)) float area(Rectangle * this) { return this.w*this.h; } //... //In your Obj-C methods you...
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How does the main() method work in C?

... be handled. */ extern int main(int argc, char **argv, char **envp); void __start(void) { /* This is the real startup function for the executable. It performs a bunch of library initialization. */ /* ... */ /* And then: */ exit(main(argc_from_somewhere, argv_from_somewhere, envp_from...
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Is there a function to make a copy of a PHP array to another?

... by reference. This means that: $a = array(); $b = $a; $b['foo'] = 42; var_dump($a); Will yield: array(0) { } Whereas: $a = new StdClass(); $b = $a; $b->foo = 42; var_dump($a); Yields: object(stdClass)#1 (1) { ["foo"]=> int(42) } You could get confused by intricacies such as Ar...
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Only read selected columns

...,Apr,May,Jun from file", sep = "\t") 3) With the read_*-functions from the readr-package: library(readr) dat <- read_table("data.txt", col_types = cols_only(Year = 'i', Jan = 'i', Feb = 'i', Mar = 'i', Apr = 'i', May...
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Is there a “goto” statement in bash?

... @ruakh Actually, many languages allow break LABEL_NAME;, rather than Bash's disgusting break INTEGER;. – Sapphire_Brick Jun 29 at 18:37 1 ...
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Is there a read-only generic dictionary available in .NET?

...lt;TKey, TValue> { private readonly IDictionary<TKey, TValue> _dictionary; public ReadOnlyDictionary() { _dictionary = new Dictionary<TKey, TValue>(); } public ReadOnlyDictionary(IDictionary<TKey, TValue> dictionary) { _dictionary = dict...
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What are inline namespaces for?

...e header <vector> might have looked like this: namespace std { #if __cplusplus < 1997L // pre-standard C++ inline #endif namespace pre_cxx_1997 { template <class T> __vector_impl; // implementation class template <class T> // e.g. w/o allocator argumen...
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What is the purpose of std::make_pair vs the constructor of std::pair?

What is the purpose of std::make_pair ? 7 Answers 7 ...