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How to check if a variable is null or empty string or all whitespace in JavaScript?
I need to check to see if a variable is null or has all empty spaces or is just blank ("").
12 Answers
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How to delete a file or folder?
How do I delete a file or folder in Python?
13 Answers
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What are Aggregates and PODs and how/why are they special?
...ing the first part in its entirety. The notion of aggregates is essential for defining PODs. If you find any errors (even minor, including grammar, stylistics, formatting, syntax, etc.) please leave a comment, I'll edit.
This answer applies to C++03. For other C++ standards see:
C++11 changes
C+...
What are the use cases for selecting CHAR over VARCHAR in SQL?
...if all my values are fixed-width. But, so what? Why not just pick VARCHAR for all text fields just to be safe.
19 Answers
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How to check if array is empty or does not exist? [duplicate]
What's the best way to check if an array is empty or does not exist?
1 Answer
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Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
...IT datatype to represent boolean data. A BIT field's value is either 1, 0, or null.
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Difference between
...r because any of the lists that could be assigned to foo3 contain a Number or a subclass of Number.
You can't read an Integer because foo3 could be pointing at a List<Double>.
You can't read a Double because foo3 could be pointing at a List<Integer>.
Writing - Given the above possible a...
How to convert Nonetype to int or string?
...onditions under which it gives None and determine a sensible value to use for that, with the usual conditional code:
result = could_return_none(x)
if result is None:
result = DEFAULT_VALUE
...or even...
if x == THING_THAT_RESULTS_IN_NONE:
result = DEFAULT_VALUE
else:
result = could_...
Should I use past or present tense in git commit messages? [closed]
...ommit messages should be in the imperative present tense, e.g. "Add tests for x". I always find myself using the past tense, e.g. "Added tests for x" though, which feels a lot more natural to me.
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Determine if Python is running inside virtualenv
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The most reliable way to check for this is to check whether sys.prefix == sys.base_prefix. If they are equal, you are not in a virtual environment; if they are unequal, you are. Inside a virtual environment, sys.prefix points to the virtual environment, and...