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(Built-in) way in JavaScript to check if a string is a valid number
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A very important note about parseInt is that it will allow you to specify a radix for converting the string to an int. This is a big gotcha as it tries to guess a radix for you if you don't supply it. So, for example: parseInt("17") results in 17 (decimal, 10), but parseInt("...
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 open a URL in a new Tab using JavaScript or jQuery? [duplicate]
How to open a URL in new tab instead of new window programatically?
6 Answers
6
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How do I calculate the date in JavaScript three months prior to today?
...ch 31st the same day as one month before March 28th, 3 days earlier? This all depends on what you mean by "one month before". Go have a conversation with your product owner.
If you want to do like momentjs does, and correct these last day of the month errors by moving to the last day of the month...
What is the difference between a Docker image and a container?
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An instance of an image is called a container. You have an image, which is a set of layers as you describe. If you start this image, you have a running container of this image. You can have many running containers of the same image.
You can see all you...
Referring to the null object in Python
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SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
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....
Semantic Issue: Property's synthesized getter follows Cocoa naming convention for returning 'owned'
... the memory management rules for declared properties, too — more specifically, for declared properties’ accessors:
You take ownership of an object if you create it using a method whose name begins with “alloc”, “new”, “copy”, or “mutableCopy”.
A property named newTitle, whe...
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:
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jQuery: How can i create a simple overlay?
How can I create a really basic overlay in jQuery without UI?
7 Answers
7
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