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How to read a large file - line by line?
... The for line in f treats the file object f as an iterable, which automatically uses buffered I/O and memory management so you don't have to worry about large files.
There should be one -- and preferably only one -- obvious way to do it.
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Argparse: Required arguments listed under “optional arguments”?
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Parameters starting with - or -- are usually considered optional. All other parameters are positional parameters and as such required by design (like positional function arguments). It is possible to require optional arguments, but this is a bit against their desig...
How to inspect the return value of a function in GDB?
...4-yellowdog-linux-gnu"...
(no debugging symbols found)
Using host libthread_db library "/lib64/libthread_db.so.1".
(gdb) break __libc_start_main
Breakpoint 1 at 0x10013cb0
(gdb) r
Starting program: /bin/ls
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
(no de...
How to TryParse for Enum value?
....Val1|MyEnum.Val2" which is a combination of two enum values. If you just call Enum.IsDefined with this string, it will return false, even though Enum.Parse handles it correctly.
Update
As mentioned by Lisa and Christian in the comments, Enum.TryParse is now available for C# in .NET4 and up.
MSDN...
What differences, if any, between C++03 and C++11 can be detected at run-time?
...onstrate breaking changes. The following is a tweaked testcase, which initially was used to demonstrate such a change, but now is used to test for C++0x or C++03.
struct X { };
struct Y { X x1, x2; };
struct A { static X B(int); };
typedef A B;
struct C : A {
using ::B::B; // (inheriting const...
Get the first element of each tuple in a list in Python [duplicate]
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Use a list comprehension:
res_list = [x[0] for x in rows]
Below is a demonstration:
>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>
Alternately, you could use unpacking instead of x[0]:
res_li...
What happens to a detached thread when main() exits?
..._local) variables of other threads nor static objects.
This appears to be allowed to allow thread managers as static objects (note in [basic.start.term]/4 says as much, thanks to @dyp for the pointer).
Problems arise when the destruction of static objects has finished, because then execution enter...
Downloading a picture via urllib and python
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Note for Python 3 it's actually import urllib.request urllib.request.urlretrieve("http://...jpg", "1.jpg"). It's urlretrieve now as of 3.x.
– user1032613
Mar 16 '18 at 0:18
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What is the list of valid @SuppressWarnings warning names in Java?
...pends on your IDE or compiler.
Here is a list for Eclipse Galileo:
all to suppress all warnings
boxing to suppress warnings relative to boxing/unboxing operations
cast to suppress warnings relative to cast operations
dep-ann to suppress warnings relative to deprecated annotation
depr...
Java 8 forEach with index [duplicate]
... way to build a forEach method in Java 8 that iterates with an index? Ideally I'd like something like this:
3 Answers
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