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How to check a not-defined variable in JavaScript
...nly be done with try/catch, since typeof will treat an undeclared variable and a variable declared with the value of undefined as equivalent.
But, to check if a variable is declared and is not undefined:
if (yourvar !== undefined) // Any scope
Previously, it was necessary to use the typeof opera...
compilation warning: no rule to process file for architecture i386
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Click on your project, and check that this file is not present in the tab Build Phases. Normally no header files should stay here. Clean and build it again, it should work!
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Equivalent of strace -feopen < command > on mac os X
...l for debugging (hence programming related). On linux, we can use the command
1 Answer
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How to copy data to clipboard in C#
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There are two classes that lives in different assemblies and different namespaces.
WinForms: use following namespace declaration, make sure Main is marked with [STAThread] attribute:
using System.Windows.Forms;
WPF: use following namespace declaration
using System.Windows;
co...
problem with and :after with CSS in WebKit
...n a select box with the pseudo :after (to style my select box with 2 parts and without images). Here's the HTML:
9 Answers
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Google Maps API v3: How to remove all markers?
... The markers are still kept in the array though so it will grow larger and larger. Would suggest clearing the array as well after the loop
– Ami
Oct 5 '12 at 9:08
5
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How do you reindex an array in PHP?
... answered Feb 26 '09 at 16:07
Andrew MooreAndrew Moore
85.1k2929 gold badges156156 silver badges172172 bronze badges
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Rails: redirect_to with :error, but flash[:error] empty
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As stated in the Rails API only :notice and :alert are by default applied as a flash hash value. If you need to set the :error value, you can do it like this:
redirect_to show_path, flash: { error: "Insufficient rights!" }
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Update date + one year in mysql
...und.
Should you want to add more complex time periods, for example 1 year and 15 days, you can use
UPDATE tablename SET datefieldname = curdate() + INTERVAL 15 DAY + INTERVAL 1 YEAR;
I found that using DATE_ADD doesn't allow for adding more than one interval. And there is no YEAR_DAYS interval k...
How to remove the lines which appear on file B from another file A?
...le1 file2 > file3 will output contents in file1 not in file2, to file3. And then mv file3 file1 would finally clear redundant contents in file1.
– Spectral
Jul 17 '14 at 20:48
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