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Rails: Open link in new tab (with 'link_to')

... The target: :_blank parameter should be a parameter of link_to, whereas you put it in image_tag parameters. Modify your code like this: <%= link_to image_tag("facebook.png", class: :facebook_icon, alt: "Facebook"), "http://www.facebo...
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What does send() do in Ruby?

... some method reacts (because its name matches the first argument). Practically speaking, those lines are equivalent: 1.send '+', 2 1.+(2) 1 + 2 Note that send bypasses visibility checks, so that you can call private methods, too (useful for unit testing). If there is really no variable before...
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Assignment in an if statement

... = value as T; if (t != null) { action(t); } } Then call it with: animal.AsIf<Dog>(dog => { // Use dog in here }); Alternatively, you could combine the two: public static void AsIf<T>(this object value, Action<T> action) where T : class { // EVI...
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Should switch statements always contain a default clause?

...e back), I was told that it's good practice to include a default clause in all switch statements. I recently remembered this advice but can't remember what the justification was. It sounds fairly odd to me now. ...
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How does “cat

... This is called heredoc format to provide a string into stdin. See https://en.wikipedia.org/wiki/Here_document#Unix_shells for more details. From man bash: Here Documents This type of redirection instructs the shell to read...
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How does the @property decorator work in Python?

...is just syntactic sugar; the syntax: @property def foo(self): return self._foo really means the same thing as def foo(self): return self._foo foo = property(foo) so foo the function is replaced by property(foo), which we saw above is a special object. Then when you use @foo.setter(), what you ...
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Match multiple cases classes in scala

... matcher(l: Foo): String = { l match { case A() => "A" case B(_) | C(_) => "B" case _ => "default" } } If you must, must, must extract the parameter and treat them in the same code block, you could: def matcher(l: Foo): String = { l match { case A() => "A" ca...
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How to print an exception in Python?

...rint the exception, it is better to use print(repr(e)); the base Exception.__str__ implementation only returns the exception message, not the type. Or, use the traceback module, which has methods for printing the current exception, formatted, or the full traceback. – Martijn Pi...
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How to download a file from a URL in C#?

...ethod also supports local files as 1st parameter – oo_dev Aug 22 '17 at 8:35 The MSDN doc did mention to use HttpClien...
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Handling a colon in an element ID in a CSS selector [duplicate]

...mpatibility mode. This other answer to this same question did work. basically \3A instead of \:. – Merlyn Morgan-Graham Mar 30 '12 at 2:32 ...