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C Macro definition to determine big endian or little endian machine?
...byte orders, ready to be put into a file called order32.h:
#ifndef ORDER32_H
#define ORDER32_H
#include <limits.h>
#include <stdint.h>
#if CHAR_BIT != 8
#error "unsupported char size"
#endif
enum
{
O32_LITTLE_ENDIAN = 0x03020100ul,
O32_BIG_ENDIAN = 0x00010203ul,
O32_PDP_E...
Does C have a “foreach” loop construct?
...ave a foreach, but macros are frequently used to emulate that:
#define for_each_item(item, list) \
for(T * item = list->head; item != NULL; item = item->next)
And can be used like
for_each_item(i, processes) {
i->wakeup();
}
Iteration over an array is also possible:
#define f...
Chaining multiple filter() in Django, is this a bug?
...el):
blog = models.ForeignKey(Blog)
headline = models.CharField(max_length=255)
pub_date = models.DateField()
...
objects
Assuming there are some blog and entry objects here.
queries
Blog.objects.filter(entry__headline_contains='Lennon',
entry__pub_date__year=2008)
Blog.object...
Inverse dictionary lookup in Python
...s slow as yours, because it creates a list from the dict twice.
key = dict_obj.keys()[dict_obj.values().index(value)]
Or if you prefer brevity over readability you can save one more character with
key = list(dict_obj)[dict_obj.values().index(value)]
And if you prefer efficiency, @PaulMcGuire's...
Python read-only property
...he new-style classes.
Example:
>>> class A(object):
... def __init__(self, a):
... self._a = a
...
... @property
... def a(self):
... return self._a
...
>>> a = A('test')
>>> a.a
'test'
>>> a.a = 'pleh'
Traceback (most recent call la...
What do I use for a max-heap implementation in Python?
...y heapq, and that there is no good alternative.
– ire_and_curses
Jun 10 '10 at 17:46
24
@gatoatig...
How to automatically generate a stacktrace when my program crashes
...nclude <unistd.h>
void handler(int sig) {
void *array[10];
size_t size;
// get void*'s for all entries on the stack
size = backtrace(array, 10);
// print out all the frames to stderr
fprintf(stderr, "Error: signal %d:\n", sig);
backtrace_symbols_fd(array, size, STDERR_FILENO)...
StringBuilder vs String concatenation in toString() in Java
...tes that this is optional. In fact, I just did a simple test with JRE 1.6.0_15 and I didn't see any compiler optimization in the decompiled class.
– bruno conde
Oct 7 '09 at 16:07
...
In which situations do we need to write the __autoreleasing ownership qualifier under ARC?
...
You're right. As the official documentation explains:
__autoreleasing to denote arguments that are passed by reference (id *) and are autoreleased on return.
All of this is very well explained in the ARC transition guide.
In your NSError example, the declaration means __stron...
How to include PHP files that require an absolute path?
...
This should work
$root = realpath($_SERVER["DOCUMENT_ROOT"]);
include "$root/inc/include1.php";
Edit: added imporvement by aussieviking
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