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Array.push() if does not exist?
How can I push into an array if neither values exist? Here is my array:
23 Answers
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How to check if a python module exists without importing it
I need to know if a python module exists, without importing it.
13 Answers
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What’s the best way to check if a file exists in C++? (cross platform)
I have read the answers for What's the best way to check if a file exists in C? (cross platform) , but I'm wondering if there is a better way to do this using standard c++ libs? Preferably without trying to open the file at all.
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How to check if a list is empty in Python? [duplicate]
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if not myList:
print "Nothing here"
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Check if Python Package is installed
What's a good way to check if a package is installed while within a Python script? I know it's easy from the interpreter, but I need to do it within a script.
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What is the pythonic way to detect the last element in a 'for' loop?
...ial case instead of the last one:
first = True
for data in data_list:
if first:
first = False
else:
between_items()
item()
This will work for any iterable, even for those that have no len():
file = open('/path/to/file')
for line in file:
process_line(line)
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How to avoid isset() and empty()
... mean you should.
These warnings are there to help you, not to annoy you. If you get a warning "You're trying to work with something that doesn't exist!", your reaction should be "Oops, my bad, let me fix that ASAP." How else are you going to tell the difference between "variables that work just fi...
What is the difference between the | and || or operators?
...th in C# and PHP. Occasionally I see a single pipe used: | . What is the difference between those two usages? Are there any caveats when using one over the other or are they interchangeable?
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Is it possible only to declare a variable without assigning any value in Python?
...oesn't mean that you won't end up with incorrectly initialized variables. If you init something to None, make sure that's what you really want, and assign something more meaningful if you can.
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Check if a file exists with wildcard in shell script [duplicate]
I'm trying to check if a file exists, but with a wildcard. Here is my example:
21 Answers
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