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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. share ...
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Printing without newline (print 'a',) prints a space, how to remove?

... you to set an end parameter. You can use it in >=2.6 by importing from __future__. I'd avoid this in any serious 2.x code though, as it will be a little confusing for those who have never used 3.x. However, it should give you a taste of some of the goodness 3.x brings. >>> from __futur...
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What is the canonical way to check for errors using the CUDA runtime API?

...on and wrapper macro like this: #define gpuErrchk(ans) { gpuAssert((ans), __FILE__, __LINE__); } inline void gpuAssert(cudaError_t code, const char *file, int line, bool abort=true) { if (code != cudaSuccess) { fprintf(stderr,"GPUassert: %s %s %d\n", cudaGetErrorString(code), file, lin...
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performSelector may cause a leak because its selector is unknown

... should simply be ignored, and it's easy to work around. Here's how: if (!_controller) { return; } SEL selector = NSSelectorFromString(@"someMethod"); IMP imp = [_controller methodForSelector:selector]; void (*func)(id, SEL) = (void *)imp; func(_controller, selector); Or more tersely (though hard...
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One-liner to check whether an iterator yields at least one element?

...In case the iterator yields something false-ish you can write any(True for _ in iterator). share | improve this answer | follow | ...
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Saving an Object (Data persistence)

...tion of it to your example: import pickle class Company(object): def __init__(self, name, value): self.name = name self.value = value with open('company_data.pkl', 'wb') as output: company1 = Company('banana', 40) pickle.dump(company1, output, pickle.HIGHEST_PROTOCOL) ...
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Bulk insert with SQLAlchemy ORM

... = [ User(name="u1"), User(name="u2"), User(name="u3") ] s.bulk_save_objects(objects) s.commit() Here, a bulk insert will be made. share | improve this answer | ...
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Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]

...ng the ZIP implementation would like to access the data directly): struct __attribute__((__packed__)) LocalFileHeader { uint32_t signature; uint16_t minVersion, flag, method, modTime, modDate; uint32_t crc32, compressedSize, uncompressedSize; uint16_t nameLength, extraLength; }; T...
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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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Append an object to a list in R in amortized constant time, O(1)?

... 2-element vector named c as is clearly intended! – j_random_hacker Dec 5 '11 at 16:45 7 So is th...