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What is the best way to create constants in Objective-C

...he file in the Reddit-Prefix.pch file to make the constants available to all the files. Is it a good way of doing things? Also, I've done my research and found several methods to create constants, but I don't know which one to use: ...
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Test PHP headers with PHPUnit

...78 Error: Class 'PHPUnit_Util_Configuration' not found in - on line 378 Call Stack: 0.0013 582512 1. {main}() -:0 Try add this to your bootstrap file to fix it: <?php if (!defined('PHPUNIT_COMPOSER_INSTALL')) { define('PHPUNIT_COMPOSER_INSTALL', __DIR__ . '/path/to/composer/ven...
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What is a regular expression for a MAC Address?

...at" comes from Wikipedia, not the 802.3 standards body. IEEE 802-2014 actually specifies hyphens for ordinary MAC addresses (§ 8.1 ¶ 3) and colons for the obsolescent bit-reversed notation (¶ 4). Importantly, in practice, no one observes this. We simply use one or the other, but never mix them...
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Adding new column to existing DataFrame in Python pandas

... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable. – Paniz Apr 27 '19 at 22:42 ...
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Why does “_” (underscore) match “-” (hyphen)?

...you are in a pattern context. e.g. inside a LIKE statement. When replacing all _ with an - : UPDATE sys_file set identifier = REPLACE(identifier, '_', '-') WHERE identifier LIKE '%\_%';. Notice the escaping inside LIKE and no escaping inside REPLACE. (I find it strange though that you are not in a p...
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Immutable vs Mutable types

... Almost, but not exactly. Technically, all variables are passed by reference in Python, but have a semantics more like pass by value in C. A counterexample to your analogy is if you do def f(my_list): my_list = [1, 2, 3]. With pass-by-reference in C, the val...
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Can a C# lambda expression have more than one statement?

... (I'm assuming you're really talking about multiple statements rather than multiple lines.) You can use multiple statements in a lambda expression using braces, but only the syntax which doesn't use braces can be converted into an expression tree: ...
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How to write header row with csv.DictWriter?

...ion "functionality", I'd prefer to code it myself; that way you can report ALL "extras" with the keys and values, not just the first extra key. What is a real nuisance with DictWriter is that if you've verified the keys yourself as each dict was being built, you need to remember to use extrasaction=...
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What's the better (cleaner) way to ignore output in PowerShell? [closed]

...ad and > $null has about a 0.3% overhead. Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different: Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]}) And no...
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Client on node: Uncaught ReferenceError: require is not defined

... true when the browser window (where this HTML file is embedded) was originally created in the main process. function createAddItemWindow() { //Create new window addItemWindown = new BrowserWindow({ width: 300, height: 200, title: 'Add Item', //The lines below solved the issue ...