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Why is “if not someobj:” better than “if someobj == None:” in Python?
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In the first test, Python try to convert the object to a bool value if it is not already one. Roughly, we are asking the object : are you meaningful or not ? This is done using the following algorithm :
If the object has a __nonzero__ special method (as do numeric built-ins, int and float),...
Using an if statement to check if a div is empty
I'm trying to remove a specific div if a separate div is empty. Here's what I'm using:
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JavaScript check if variable exists (is defined/initialized)
Which method of checking if a variable has been initialized is better/correct?
(Assuming the variable could hold anything (string, int, object, function, etc.))
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How to implement not with if statement in Ember Handlebars?
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Also keep in mind that you can insert an {{else}} in between an {{#if}} or {{#unless}} and the closing tag.
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Is there a VB.NET equivalent for C#'s '??' operator?
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Use the If() operator with two arguments (Microsoft documentation):
' Variable first is a nullable type.
Dim first? As Integer = 3
Dim second As Integer = 6
' Variable first <> Nothing, so its value, 3, is returned.
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How to check if a symlink exists
I'm trying to check if a symlink exists in bash. Here's what I've tried.
8 Answers
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One line if statement not working
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Remove if from if @item.rigged ? "Yes" : "No"
Ternary operator has form condition ? if_true : if_false
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How do I tell if a regular file does not exist in Bash?
I've used the following script to see if a file exists:
20 Answers
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PHP - How to check if a string contains a specific text [duplicate]
Suppose I have the code above, how to write the statement "if($a exist 'some text')"?
8 Answers
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Check if $_POST exists
I'm trying to check whether a $_POST exists and if it does, print it inside another string, if not, don't print at all.
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