大约有 40,000 项符合查询结果（耗时：0.0334秒） [XML]
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...
Yes, __attribute__((packed)) is potentially unsafe on some systems. The symptom probably won't show up on an x86, which just makes the problem more insidious; testing on x86 systems won't reveal the problem. (On the x86, misaligned accesses are handled in hardwa...
How to implement an ordered, default dict? [duplicate]
...deredDict() and defaultdict() from collections in one object, which shall be an ordered, default dict .
Is this possible?
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How can I rename a field for all documents in MongoDB?
...above are: { upsert:false, multi:true }. You need the multi:true to update all your records.
Or you can use the former way:
remap = function (x) {
if (x.additional){
db.foo.update({_id:x._id}, {$set:{"name.last":x.name.additional}, $unset:{"name.additional":1}});
}
}
db.foo.find().forEach...
UnicodeDecodeError: 'ascii' codec can't decode byte 0xef in position 1
...;> s1 = s.decode('utf-8')
>>> print s1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode characters in position 1-5: ordinal not in range(128)
>>>
Consult the docs for your linux variant to disc...
Qt: can't find -lGL error
I just reinstalled QtCreator, created new project ( Qt Application ) an got this after compilation:
8 Answers
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How to easily map c++ enums to strings
...xtra syntactic sugar, here's how to write a map_init class. The goal is to allow
std::map<MyEnum, const char*> MyMap;
map_init(MyMap)
(eValue1, "A")
(eValue2, "B")
(eValue3, "C")
;
The function template <typename T> map_init(T&) returns a map_init_helper<T>.
map...
How to remove illegal characters from path and filenames?
...gal path into a legitimate but probably unintended one.
Edit: Or a potentially 'better' solution, using Regex's.
string illegal = "\"M\"\\a/ry/ h**ad:>> a\\/:*?\"| li*tt|le|| la\"mb.?";
string regexSearch = new string(Path.GetInvalidFileNameChars()) + new string(Path.GetInvalidPathChars());
...
Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...
RE error: illegal byte sequence on Mac OS X
...t a valid UTF-8 char.
Note that, by contrast, GNU sed (Linux, but also installable on macOS) simply passes the invalid byte through, without reporting an error.
Using the formerly accepted answer is an option if you don't mind losing support for your true locale (if you're on a US system and you ne...
Checking if a double (or float) is NaN in C++
...nly if f is NaN.
Note that, as some comments below have pointed out, not all compilers respect this when optimizing code.
For any compiler which claims to use IEEE floating point, this trick should work. But I can't guarantee that it will work in practice. Check with your compiler, if in doubt.
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