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How to check null objects in jQuery
...em to have enough reputation to vote down the answer...)
Wolf wrote:
Calling length property on undefined
or a null object will cause IE and
webkit browsers to fail!
Instead try this:
// NOTE!! THE FOLLOWING IS WRONG; DO NOT USE! -- EleotleCram
if($("#something") !== null){
// do ...
How to make lists contain only distinct element in Python? [duplicate]
...ving
return list(_f(seq, idfun))
def _f(seq, idfun=None):
''' Originally proposed by Andrew Dalke '''
seen = set()
if idfun is None:
for x in seq:
if x not in seen:
seen.add(x)
yield x
else:
for x in seq:
x = idfun(x)
if x not in seen:
s...
Proper way to use **kwargs in Python
...*kwargs):
...etc...
this is not true. In the latter case, f can be called as f(23, 42), while the former case accepts named arguments only -- no positional calls. Often you want to allow the caller maximum flexibility and therefore the second form, as most answers assert, is preferable: but ...
ERROR 1130 (HY000): Host '' is not allowed to connect to this MySQL server [duplicate]
...vileges:
CREATE USER 'root'@'ip_address' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'root'@'ip_address';
If you see %, well then, there's another problem altogether as that is "any remote source". If however you do want any/all systems to connect via root, use the % wildcard to gra...
Spring Data JPA find by embedded object property
...
According to me, Spring doesn't handle all the cases with ease. In your case
the following should do the trick
Page<QueuedBook> findByBookIdRegion(Region region, Pageable pageable);
or
Page<QueuedBook> findByBookId_Region(Region region, Pageable ...
How to detect iPhone 5 (widescreen devices)?
...
First of all, you shouldn't rebuild all your views to fit a new screen, nor use different views for different screen sizes.
Use the auto-resizing capabilities of iOS, so your views can adjust, and adapt any screen size.
That's not v...
Mocking a class: Mock() or patch()?
...ake a look at this snippet:
>>> class MyClass(object):
... def __init__(self):
... print 'Created MyClass@{0}'.format(id(self))
...
>>> def create_instance():
... return MyClass()
...
>>> x = create_instance()
Created MyClass@4299548304
>>>
>>>...
What are the “standard unambiguous date” formats for string-to-date conversion in R?
...te (+1). However, the error message "standard unambiguous format" is ironically ambiguous, to which the 23 previous questions attest. A more direct error message like, "format not recognized, see documentation" might improve user experience. Also, I don't believe "01/01/2000" is ISO-8601 ("2000-01-0...
How to limit the amount of concurrent async I/O operations?
... Stephen Toub, but the less announced news is that the async semaphore actually made it into the Beta release of .NET 4.5
If you look at our beloved SemaphoreSlim class (which you should be using since it's more performant than the original Semaphore), it now boasts the WaitAsync(...) series of ove...
How to tell if JRE or JDK is installed
I have one computer that I intentionally installed JDK on. I have another computer with JRE, for, among other things, testing. However, when I got a java application working on this computer, and then tried it on another, it complained that JDK was required. How can I check if JDK was somehow instal...