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How do I check if an object has a specific property in JavaScript?
...give you completely misleading results.
It depends on what you're looking for. If you want to know if an object physically contains a property (and it is not coming from somewhere up on the prototype chain) then object.hasOwnProperty is the way to go. All modern browsers support it. (It was missing...
What's the difference between using CGFloat and float?
...d to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with this. CGFloat seems to be something "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference?
...
Traverse a list in reverse order in Python
... reversed() function:
>>> a = ["foo", "bar", "baz"]
>>> for i in reversed(a):
... print(i)
...
baz
bar
foo
To also access the original index, use enumerate() on your list before passing it to reversed():
>>> for i, e in reversed(list(enumerate(a))):
... print(...
When saving, how can you check if a field has changed?
...gs, **kwargs)
self.__original_name = self.name
def save(self, force_insert=False, force_update=False, *args, **kwargs):
if self.name != self.__original_name:
# name changed - do something here
super(Person, self).save(force_insert, force_update, *args, **kwa...
How to read a single character from the user?
Is there a way of reading one single character from the user input? For instance, they press one key at the terminal and it is returned (sort of like getch() ). I know there's a function in Windows for it, but I'd like something that is cross-platform.
...
Understanding Python super() with __init__() methods [duplicate]
...ildB(Base):
def __init__(self):
mro = type(self).mro()
for next_class in mro[mro.index(ChildB) + 1:]: # slice to end
if hasattr(next_class, '__init__'):
next_class.__init__(self)
break
If we didn't have the super object, we'd have to ...
Detect URLs in text with JavaScript
Does anyone have suggestions for detecting URLs in a set of strings?
13 Answers
13
...
django urls without a trailing slash do not redirect
...sed if CommonMiddleware is installed...". I prefer Michael Gendin's answer for a cleaner solution.
– Wtower
Feb 11 '15 at 9:26
...
Detect blocked popup in Chrome
...g similar), you could use the ready() event (or something similar) to wait for the DOM to load before checking the window offset. The danger in this is that Safari detection works in a conflicting way: the popup's DOM will never be ready() in Safari because it'll give you a valid handle for the wind...
How do I convert between big-endian and little-endian values in C++?
... do the following: You include intrin.h and call the following functions:
For 16 bit numbers:
unsigned short _byteswap_ushort(unsigned short value);
For 32 bit numbers:
unsigned long _byteswap_ulong(unsigned long value);
For 64 bit numbers:
unsigned __int64 _byteswap_uint64(unsigned __int64 ...