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Build a Basic Python Iterator
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Iterator objects in python conform to the iterator protocol, which basically means they provide two methods: __iter__() and __next__().
The __iter__ returns the iterator object and is implicitly called
at the start of loops.
The __next__() method returns the next value and is implicitly cal...
Understanding the difference between __getattr__ and __getattribute__
...oesn't explicitly manage and do that via __getattr__ method.
Python will call this method whenever you request an attribute that hasn't already been defined, so you can define what to do with it.
A classic use case:
class A(dict):
def __getattr__(self, name):
return self[name]
a = A()...
Convert Django Model object to dict with all of the fields intact
How does one convert a Django Model object to a dict with all of its fields? All ideally includes foreign keys and fields with editable=False .
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Xcode stops working after set “xcode-select -switch”
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You should be pointing it towards the Developer directory, not the Xcode application bundle. Run this:
sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer
With recent versions of Xcode, you can go to Xcode ➙ Preferences… ➙ Locations and pick one of the options for Comma...
How to get the parents of a Python class?
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If you want all the ancestors rather than just the immediate ones, use inspect.getmro:
import inspect
print inspect.getmro(cls)
Usefully, this gives you all ancestor classes in the "method resolution order" -- i.e. the order in which ...
How to select where ID in Array Rails ActiveRecord without exception
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If it is just avoiding the exception you are worried about, the "find_all_by.." family of functions works without throwing exceptions.
Comment.find_all_by_id([2, 3, 5])
will work even if some of the ids don't exist. This works in the
user.comments.find_all_by_id(potentially_nonexistent_id...
Setting environment variables via launchd.conf no longer works in OS X Yosemite/El Capitan/macOS Sie
...iables will not be set (so you'll need to set them in ~/.bash_profile). Finally, this doesn't seem to work for PATH on El Capitan and Sierra. That needs to be set via 'launchctl config user path ...' and in /etc/paths.
share...
What is the difference between a route and resource in New Router API?
... a brand new
namespace. That namespace is named after the
resource and all of the child routes will be inserted into it.
Update: more complex example with nested resources
Consider the following more complex example with multiple nested resources:
App.Router.map(function() {
this.resource(...
getResourceAsStream() vs FileInputStream
I was trying to load a file in a webapp, and I was getting a FileNotFound exception when I used FileInputStream . However, using the same path, I was able to load the file when I did getResourceAsStream() .
What is the difference between the two methods, and why does one work while the other do...
Is it possible to add an HTML link in the body of a MAILTO link [duplicate]
...-link it either before sending, or at the other end when receiving.
For really long urls that will likely wrap due to all the parameters, wrap the link in a less than/greater than symbol. This tells the email client not to wrap the url.
e.g.
<http://www.example.com/foo.php?this=a&really...