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How to make a JSONP request from Javascript without JQuery?
...ng jQuery or other external library? I would like to use JavaScript itself and then parse the data and make it an object so I could use it. Do I have to use an external library? If not, how can I do it?
...
Imitate Facebook hide/show expanding/contracting Navigation Bar
...wing property:
@property (nonatomic) CGFloat previousScrollViewYOffset;
And here are the UIScrollViewDelegate methods:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGRect frame = self.navigationController.navigationBar.frame;
CGFloat size = frame.size.height - 21;
CGFloat...
Why is using 'eval' a bad practice?
...few reasons:
There is almost always a better way to do it
Very dangerous and insecure
Makes debugging difficult
Slow
In your case you can use setattr instead:
class Song:
"""The class to store the details of each song"""
attsToStore=('Name', 'Artist', 'Album', 'Genre', 'Location')
d...
Remove duplicate dict in list in Python
I have a list of dicts, and I'd like to remove the dicts with identical key and value pairs.
12 Answers
...
Creating an abstract class in Objective-C
...ct class - by making the methods/ selectors call doesNotRecognizeSelector: and therefore raise an exception making the class unusable.
For example:
- (id)someMethod:(SomeObject*)blah
{
[self doesNotRecognizeSelector:_cmd];
return nil;
}
You can also do this for init.
...
Getting the class name of an instance?
...
This is used often enough in logging, orm and framework code that there really should be a builtin typename(x) ... requiring a user to look at the "guts" to get a name isn't terribly pythonic, IMO.
– Erik Aronesty
Apr 18 '18 at ...
How to write an async method with out parameter?
...el CLR rewrite instead of a
compiler-rewrite. We examined that approach, and it had a lot going
for it, but it would ultimately have been so costly that it'd never
have happened.
A typical workaround for this situation is to have the async method return a Tuple instead.
You could re-write yo...
How to 'insert if not exists' in MySQL?
I started by googling, and found this article which talks about mutex tables.
10 Answers
...
Check if Python Package is installed
... a python script, just do something like this:
Python 3.3+ use sys.modules and find_spec:
import importlib.util
import sys
# For illustrative purposes.
name = 'itertools'
if name in sys.modules:
print(f"{name!r} already in sys.modules")
elif (spec := importlib.util.find_spec(name)) is not None...
What's the difference between dependencies, devDependencies and peerDependencies in npm package.json
This documentation answers my question very poorly. I didn't understand those explanations. Can someone say in simpler words? Maybe with examples if it's hard to choose simple words?
...