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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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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)
#...
(Built-in) way in JavaScript to check if a string is a valid number
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To check if a variable (including a string) is a number, check if it is not a number:
This works regardless of whether the variable content is a string or number.
isNaN(num) // returns true if the variable does NOT contain a...
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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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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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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How to make “if not true condition”?
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try
if ! grep -q sysa /etc/passwd ; then
grep returns true if it finds the search target, and false if it doesn't.
So NOT false == true.
if evaluation in shells are designed to be very flexible, and many times doesn't require...
How to detect Windows 64-bit platform with .NET?
...onment.Is64BitOperatingSystem.
IntPtr.Size won't return the correct value if running in 32-bit .NET Framework 2.0 on 64-bit Windows (it would return 32-bit).
As Microsoft's Raymond Chen describes, you have to first check if running in a 64-bit process (I think in .NET you can do so by checking IntP...