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Determine if variable is defined in Python [duplicate]
...ime? This is not always obvious because (1) the variable could be conditionally set, and (2) the variable could be conditionally deleted. I'm looking for something like defined() in Perl or isset() in PHP or defined? in Ruby.
...
How do I replace whitespaces with underscore?
...s, such as \t or a non-breaking space.
– Roberto Bonvallet
Jun 17 '09 at 15:49
13
Yes you are cor...
how to use javascript Object.defineProperty
...rs = new Product("Sneakers",20);
sneakers.discount = 50; // 50, setter is called
sneakers.discount+= 20; // 70, setter is called
sneakers.discount+= 20; // 80, not 90!
alert(sneakers.discount); // getter is called
Note the last but one line: the responsibility for correct discount value was moved ...
How to redirect to a 404 in Rails?
...ou want to show a 404 page, create a render_404 method (or not_found as I called it) in ApplicationController like this:
def not_found
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way....
Android - Launcher Icon Size
...n? Should I have to create 9-Patch images for the icon to scale automatically, or would it be better to create separate icons?
...
SQLAlchemy: cascade delete
...use that is where you defined your relationship (it doesn't care that you called it "Child" of course).
If you define the relationship on the Parent class instead, it will work:
children = relationship("Child", cascade="all,delete", backref="parent")
(note "Child" as a string: this is allowed wh...
How to manage client-side JavaScript dependencies? [closed]
...anage dependencies on the server side, I could not find any that satisfies all my needs to have a coherent client side JavaScript dependency management workflow. I want to satisfy these 5 requirements:
...
Remove not alphanumeric characters from string
...e them.
A backslash in the string needs escaping if it's to be taken literally:
"\\test\\red\\bob\\fred\\new".replace(/\W/g, '')
"testredbobfrednew" // output
Handling malformed strings
If you're not able to escape the input string correctly (why not?), or it's coming from some kind of untruste...
Django get the static files URL in view
...lean way of adding the hostname to the static url (if not present in STATIC_URL)? I need to add images or other resources in mails, where the user won't be able to find the resources with relative urls.
– gepatino
Sep 12 '13 at 20:00
...
Python debugging tips [closed]
... same effect in the running code
ipdb is a version of pdb for IPython. It allows the use of pdb with all the IPython features including tab completion.
It is also possible to set pdb to automatically run on an uncaught exception.
Pydb was written to be an enhanced version of Pdb. Benefits?
...