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How to access object attribute given string corresponding to name of that attribute
...ay prefer to use a generalized getter method like so:
class Test:
def __init__(self):
self.attr1 = 1
self.attr2 = 2
def get(self,varname):
return getattr(self,varname)
t = Test()
x = "attr1"
print ("Attribute value of {0} is {1}".format(x, t.get(x)))
Outputs:
At...
PHP Fatal error: Cannot redeclare class
...ious repetition like this (even in quite a complex situation). The include_once tip helps to clarify an obscure feature of PHP.
– DavidHyogo
Mar 20 '13 at 2:12
2
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Weak and strong property setter attributes in Objective-C
...n release autorelease etc... Instead you use strong weak for properties or __strong
__weak
for variables (defaults to __strong). Strong is the equivalent to retain, however ARC will manage the release for you.
The only time you would want to use weak, is if you wanted to avoid retain cycles (e.g...
Hide keyboard when scroll UITableView
...to our UITableViewController class
override func scrollViewDidScroll(_ scrollView: UIScrollView) {
if !tableView.isDecelerating {
view.endEditing(true)
}
}
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Why is there no xrange function in Python3?
...tion has nothing to do with it. (Not surprising, as a one-time call to the __iter__ slot isn't likely to be visible among 10000000 calls to whatever happens in the loop, but someone brought it up as a possibility.)
But it's only 30% slower. How did the OP get 2x as slow? Well, if I repeat the same ...
Are HLists nothing more than a convoluted way of writing tuples?
...)
// Publish their `HListIso`'s
implicit def fooIso = Iso.hlist(Foo.apply _, Foo.unapply _)
implicit def barIso = Iso.hlist(Bar.apply _, Bar.unapply _)
// And now they're monoids ...
implicitly[Monoid[Foo]]
val f = Foo(13, "foo") |+| Foo(23, "bar")
assert(f == Foo(36, "foobar"))
implicitly[Monoi...
Running python script inside ipython
...
from within the directory of "my_script.py" you can simply do:
%run ./my_script.py
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What's the difference between lists and tuples?
...e pairs of page and line number to reference locations in a book, e.g.:
my_location = (42, 11) # page number, line number
You can then use this as a key in a dictionary to store notes on locations. A list on the other hand could be used to store multiple locations. Naturally one might want to ad...
Download the Android SDK components for offline install
...available
Fetching https://dl-ssl.google.com/android/repository/addons_list-2.xml
Fetched Add-ons List successfully
Fetching URL: https://dl-ssl.google.com/android/repository/repository-7.xml
Validate XML: https://dl-ssl.google.com/android/repository/repository-7.xml
Parse XML: https...
How does Apple know you are using private API?
...ist all linked symbols. This can detect
Undocumented C functions such as _UIImageWithName;
Objective-C classes such as UIProgressHUD
Ivars such as UITouch._phase (which could be the cause of rejection of Three20-based apps last few months.)
3. Listing Objective-C selectors, or strings
Objective...