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Dealing with multiple Python versions and PIP?

... recommendation because it works across all versions of Python, and in all forms of virtualenv. For example: # The system default python: $ python -m pip install fish # A virtualenv's python: $ .env/bin/python -m pip install fish # A specific version of python: $ python-3.6 -m pip install fish ...
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How to change a nullable column to not nullable in a Rails migration?

...umn => Time.now}, {:date_column => nil}). The query in your original form just made all my models have nil value in the field. – dimitarvp Aug 1 '12 at 12:16 ...
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What is the 'instanceof' operator used for in Java?

...not sure what they are. Let's say you've got a collection of controls on a form. You want to read the checked state of whatever checkboxes are there, but you can't ask a plain old object for its checked state. Instead, you'd see if each object is a checkbox, and if it is, cast it to a checkbox and c...
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Rails create or update magic?

...h, in most cases, is hardly an issue at all. So unless you have serious performance concerns, I would not use the gem. For example, if no user is found with the name "Roger", a new user instance is instantiated with its name set to "Roger". user = User.where(name: "Roger").first_or_initialize user...
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Just disable scroll not hide it?

... I'm the OP With the help of answer from fcalderan I was able to form a solution. I leave my solution here as it brings clarity to how to use it, and adds a very crucial detail, width: 100%; I add this class body.noscroll { position: fixed; overflow-y: scroll; width: 100%; }...
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javascript: Clear all timeouts?

...h is not required by specification). Althrough the starting number differs form browser to browser. It seems that Opera, Safari, Chrome and IE > 8 starts timeout ids from 1, Gecko-based browsers from 2 and IE <= 8 from some random number that is magically saved across tab refresh. You can disc...
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Make Vim show ALL white spaces as a character

...sual, to understand how listchars works, use the help. It provides great information about what chars can be displayed (like trailing space, for instance) and how to do it: :help listchars It might be helpful to add a toggle to it so you can see the changes mid editing easily (source: VIM :set li...
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ASP.NET MVC: Custom Validation by DataAnnotation

...lt; this.MinLength) { return new ValidationResult(this.FormatErrorMessage(validationContext.DisplayName)); } return null; } } and then you might have a view model and decorate one of its properties with it: public class MyViewModel { [CombinedMinLength(...
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What is stdClass in PHP?

...for booleans will be extremely old, probably written before standards were formed. Let's be honest, PHP was originally written as a complete mess without any standards (see the wide range of variable/function/object naming conventions used). I've honestly never seen any PHP code where the developer ...
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Is PHP compiled or interpreted?

... to produce bytecode for processing by the Zend Engine, giving improved performance over its interpreter predecessor. – kiranvj Jul 28 '12 at 16:17 5 ...