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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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What is the python keyword “with” used for? [duplicate]
...t in an object that supports the context management protocol (that is, has __enter__() and __exit__() methods).
Update fixed VB callout per Scott Wisniewski's comment. I was indeed confusing with with using.
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How to get position of a certain element in strings vector, to use it as an index in ints vector?
...e use size_t we must be careful not to subtract a larger iterator from a smaller iterator.
– dasblinkenlight
Oct 17 '17 at 10:49
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java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...ead:
For a supplementary character, utf8 cannot store the character at all,
while utf8mb4 requires four bytes to store it. Since utf8 cannot store
the character at all, you do not have any supplementary characters in
utf8 columns and you need not worry about converting characters or
losi...
Handling applicationDidBecomeActive - “How can a view controller respond to the app becoming Active?
...tionDidBecomeActiveNotification and specify which method that you want to call when that notification gets sent to your application.
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(someMethod:)
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When to use symbols instead of strings in Ruby?
...iers. For Ruby < 2.2 only use symbols when they aren't generated dynamically, to avoid memory leaks.
Full answer
The only reason not to use them for identifiers that are generated dynamically is because of memory concerns.
This question is very common because many programming languages don't h...
To ARC or not to ARC? What are the pros and cons? [closed]
...t has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)
OK, now I will...
C++对象布局及多态探索之菱形结构虚继承 - C/C++ - 清泛网 - 专注C/C++及内核技术
...0则从C100和C101多重继承而来。
struct C041
{
C041() : c_(0x01) {}
virtual void foo() { c_ = 0x02; }
char c_;
};
struct C100 : public virtual C041
{
C100() : c_(0x02) {}
char c_;
};
struct C101 : public virtual C041
{
C101() : c_(0x03) {}
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Which is faster in Python: x**.5 or math.sqrt(x)?
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I've now run it 3 times on codepad.org and all three times a() was much faster than b().
– Jeremy Ruten
Nov 29 '08 at 1:38
13
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Can I replace groups in Java regex?
I have this code, and I want to know, if I can replace only groups (not all pattern) in Java regex.
Code:
7 Answers
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