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Method Syntax in Objective-C
...I on the iPhone) is being returned. From my understanding, the Method is called ' pickerView ', and returns an NSInteger.
...
javascript set a variable if undefined
... x === 'undefined') ? your_default_value : x;
On newer browsers it's actually safe to write:
var x = (x === undefined) ? your_default_value : x;
but be aware that it is possible to subvert this on older browsers where it was permitted to declare a variable named undefined that has a defined val...
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...
Get current folder path
... that program (double-clicking on the .exe) I want the program to process all the files within the current folder where the exe file exists . How can the program determine the path in which it is currently executing?
...
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 to search a specific value in all tables (PostgreSQL)?
... at 11:55
Mike Sherrill 'Cat Recall'Mike Sherrill 'Cat Recall'
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...
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....
Virtual Memory Usage from Java under Linux, too much memory used
... a long-standing complaint with Java, but it's largely meaningless, and usually based on looking at the wrong information. The usual phrasing is something like "Hello World on Java takes 10 megabytes! Why does it need that?" Well, here's a way to make Hello World on a 64-bit JVM claim to take over 4...
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...
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...