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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
How do I list all files of a directory?
How can I list all files of a directory in Python and add them to a list ?
21 Answers
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What is the __del__ method, How to call it?
...is used, probably not like that: obj1.del() . So, my questions is how to call the __del__ method?
5 Answers
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What optimizations can GHC be expected to perform reliably?
...has a lot of optimizations that it can perform, but I don't know what they all are, nor how likely they are to be performed and under what circumstances.
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Convert from enum ordinal to enum type
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This is very worrying because arrays are mutable. Even though values[] is final, it doesn't prevent Suit.values[0] = Suit.Diamonds; somewhere in your code. Ideally that will never happen, but the overall principle of don't expose mutable fields still holds. For this a...
What is the difference between a static and a non-static initialization code block
...own, just like simple variable initializers) when the class is loaded (actually, when it's resolved, but that's a technicality).
Instance initializers are executed in the order defined when the class is instantiated, immediately before the constructor code is executed, immediately after the invocat...
How to get a function name as a string?
In Python, how do I get a function name as a string, without calling the function?
12 Answers
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Elasticsearch query to return all records
I have a small database in Elasticsearch and for testing purposes would like to pull all records back. I am attempting to use a URL of the form...
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C++ mark as deprecated
...erface that I want to deprecate with portable C++.
When I Googled for this all I got was a Microsoft specific solution; #pragma deprecated and __declspec(deprecated) .
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Prevent nginx 504 Gateway timeout using PHP set_time_limit()
... attempts to make a connection to a database and then creates many initial tables and fills it with data .. that could take quite some time before a response.
– imme
Nov 20 '17 at 18:11
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