大约有 40,000 项符合查询结果（耗时：0.0299秒） [XML]
Xcode doesn't show the line that causes a crash
...rminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSSingleObjectArrayI objectAtIndex:]: index 1 beyond bounds [0 .. 0]'
*** First throw call stack:
(
0 CoreFoundation 0x000000010e85cd4b __exceptionPreprocess + 171
1 libobjc.A.dylib ...
Try catch statements in C
...ou can simulate them to a degree with setjmp and longjmp calls.
static jmp_buf s_jumpBuffer;
void Example() {
if (setjmp(s_jumpBuffer)) {
// The longjmp was executed and returned control here
printf("Exception happened here\n");
} else {
// Normal code execution starts here
Te...
Class method decorator with self arguments?
...nstance attribute at class definition time, check it at runtime:
def check_authorization(f):
def wrapper(*args):
print args[0].url
return f(*args)
return wrapper
class Client(object):
def __init__(self, url):
self.url = url
@check_authorization
def get(...
What is a “callable”?
...allable is anything that can be called.
The built-in callable (PyCallable_Check in objects.c) checks if the argument is either:
an instance of a class with a __call__ method or
is of a type that has a non null tp_call (c struct) member which indicates callability otherwise (such as in functions,...
Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
...rgv[argc-1] represent the program parameters.
I've also used:
#if defined(_WIN32)
static size_t getExecutablePathName(char* pathName, size_t pathNameCapacity)
{
return GetModuleFileNameA(NULL, pathName, (DWORD)pathNameCapacity);
}
#elif defined(__linux__) /* elif of: #if defined(_WIN32) *...
编译不成功是什么原因？ - App Inventor 2 中文网 - 清泛IT社区，为创新赋能！
...示如下：
无法编译该项目，
编译器输出的错误信息为
________Preparing application icon
________Creating animation xml
________Creating style xml
________Creating provider_path xml
________Creating network_security_config xml
________Generating adaptive icon file
________...
Short description of the scoping rules?
...ithout explicit declaration, but writing to it without declaring global(var_name) will instead create a new local instance.
– Peter Gibson
Jun 27 '12 at 5:53
12
...
How to disable GCC warnings for a few lines of code
...
TL;DR: If it works, avoid, or use specifiers like __attribute__, otherwise _Pragma.
This is a short version of my blog article
Suppressing Warnings in GCC and Clang.
Consider the following Makefile
CPPFLAGS:=-std=c11 -W -Wall -pedantic -Werror
.PHONY: all
all: puts
fo...
How to check version of python modules?
...
I suggest using pip in place of easy_install. With pip, you can list all installed packages and their versions with
pip freeze
In most linux systems, you can pipe this to grep(or findstr on Windows) to find the row for the particular package you're interest...
UIPanGestureRecognizer - Only vertical or horizontal
...t; fabs(velocity.x);
}
And for Swift:
func gestureRecognizerShouldBegin(_ gestureRecognizer: UIPanGestureRecognizer) -> Bool {
let velocity = gestureRecognizer.velocity(in: someView)
return abs(velocity.x) > abs(velocity.y)
}
...