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Determine if variable is defined in Python [duplicate]
...eleted. I'm looking for something like defined() in Perl or isset() in PHP or defined? in Ruby.
6 Answers
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How to properly override clone method?
...ems reasonable, but you can also add a comment that explains why the catch block will never be entered in this particular case.
Alternatively, as others have also suggested, you can perhaps implement clone without calling super.clone.
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Check if an array is empty or exists
...iable hoisting. Make sure you use var whenever declaring a variable:
<?php echo "var image_array = ".json_encode($images);?>
// add var ^^^ here
And then make sure you never accidently redeclare that variable later:
else {
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image_array = []; // no var here
}
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RegEx to parse or validate Base64 data
...e : if you do so, you force the base64 string to contain at least a 4-size block, rendering valid values such as MQ== not a match to your expression
– njzk2
Oct 22 '13 at 13:47
5
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When would I use XML instead of SQL? [closed]
...used, which is storing all of my data in a (My)SQL database and then using PHP/Python/etc. to work with it on the web as needed.
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What exactly is an Assembly in C# or .NET?
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http://www.codeguru.com/columns/csharp_learning/article.php/c5845
An assembly is a file that is automatically generated by the compiler upon successful compilation of every .NET application. It can be either a Dynamic Link Library or an executable file. It is generated only once ...
How to read a file into a variable in shell?
...cessary, otherwise you're appending literal \ and n characters. Your code block also has an extra space at the end, not sure if that's intentional, but it'd indent every subsequent line with an extra whitespace.
– dimo414
Mar 27 '19 at 17:23
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What's the fastest way to delete a large folder in Windows?
...o take me for ever to use.. Oh well. Each file is only like 20 bytes. Darn PHP Session Files.
– Chrispix
Aug 28 '10 at 19:59
1
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How to link to specific line number on github
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that shift+click the second line for a block is a good one! I was manually editing the URL to add the second line :). follow up question though, what if I wanted lines 2, 4, and from 17-22 highlighted? Is that possible or can I only highlight one block at a time?
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How to read a file in reverse order?
... Watch out that this may not work as expected for text files. Getting blocks correctly in reversed order only works for binary files. The problem is that for text files with multi-byte encoding (such as utf8), seek() and read() refer to different sizes. That is probably also the reason why the ...