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OS X10.9 环境下部署 QT5.3.1 常见的编译问题 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...件中加入对应的SDK版本:
1
QMAKE_MAC_SDK = macosx10.9
3、:-1: error: [ui_mainwindow.h] Trace/BPT trap: 5
dyld: Library not loaded: /work/build/______________________________PADDING______________________________/lib/QtCore.framework/Versio...
Python: How do I make a subclass from a superclass?
...
# Initialize using Parent
#
class MySubClass(MySuperClass):
def __init__(self):
MySuperClass.__init__(self)
Or, even better, the use of Python's built-in function, super() (see the Python 2/Python 3 documentation for it) may be a slightly better method of calling the parent for ...
error LNK2019: 无法解析的外部符号 __imp__PlaySoundW@12，该符号在函数 \...
error LNK2019: 无法解析的外部符号 __imp__PlaySoundW@12，该符号在函数 "long __stdcall WndProc(struct HWND__ *,unsigned int,unsigned int,long)" (?WndProc@@YGJPAUHWND__@@IIJ@Z) 中被引用#include <mmsystem.h>#pragma comment(lib, "WINMM.LIB")
#include <mmsystem.h>
#pragma comm...
Python's equivalent of && (logical-and) in an if-statement
...actually
evaluated because of the print statements:
>>> def print_and_return(value):
... print(value)
... return value
>>> res = print_and_return(False) and print_and_return(True)
False
As you can see only one print statement is executed, so Python really didn't even lo...
Is it possible to make abstract classes in Python?
...
# Python 2
from abc import ABCMeta, abstractmethod
class Abstract:
__metaclass__ = ABCMeta
@abstractmethod
def foo(self):
pass
Whichever way you use, you won't be able to instantiate an abstract class that has abstract methods, but will be able to instantiate a subclass th...
How dangerous is it to compare floating point values?
...ince 5 is not a power of 2), as well as irrational results like the square root of anything that's not a perfect square.
Double rounding. On some systems (particularly x86), floating point expressions are evaluated in higher precision than their nominal types. This means that when one of the above t...
How do I get the full path of the current file's directory?
...3
For the directory of the script being run:
import pathlib
pathlib.Path(__file__).parent.absolute()
For the current working directory:
import pathlib
pathlib.Path().absolute()
Python 2 and 3
For the directory of the script being run:
import os
os.path.dirname(os.path.abspath(__file__))
I...
How can I get a list of all classes within current module in Python?
...
Try this:
import sys
current_module = sys.modules[__name__]
In your context:
import sys, inspect
def print_classes():
for name, obj in inspect.getmembers(sys.modules[__name__]):
if inspect.isclass(obj):
print(obj)
And even b...
Obfuscated C Code Contest 2006. Please explain sykes2.c
...
Let's de-obfuscate it.
Indenting:
main(_) {
_^448 && main(-~_);
putchar(--_%64
? 32 | -~7[__TIME__-_/8%8][">'txiZ^(~z?"-48] >> ";;;====~$::199"[_*2&8|_/64]/(_&2?1:8)%8&1
: 10);
}
Introducing variables to untan...
Does Python have an ordered set?
... the signature for .union doesn't match that of set, but since it includes __or__ something similar can easily be added:
@staticmethod
def union(*sets):
union = OrderedSet()
union.union(*sets)
return union
def union(self, *sets):
for set in sets:
self |= set
...