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How to validate an email address using a regular expression?
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The fully RFC 822 compliant regex is inefficient and obscure because of its length. Fortunately, RFC 822 was superseded twice and the current specification for email addresses is RFC 5322. RFC 5322 leads to a regex that can be understood if studied for a few minutes and is eff...
(this == null) in C#!
Due to a bug that was fixed in C# 4, the following program prints true . (Try it in LINQPad)
6 Answers
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Writing your own STL Container
Are there guidelines on how one should write new container which will behave like any STL container?
3 Answers
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jQuery SVG, why can't I addClass?
I am using jQuery SVG. I can't add or remove a class to an object. Anyone know my mistake?
15 Answers
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Browse and display files in a git repo without cloning
Is there a way to browse and display files in a git repo without cloning it first? I can do those in svn using the commands:
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How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
...ike to write a single SQL command to drop multiple columns from a single table in one ALTER TABLE statement.
11 Answers
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What does the “map” method do in Ruby?
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The map method takes an enumerable object and a block, and runs the block for each element, outputting each returned value from the block (the original object is unchanged unless you use map!):
[1, 2, 3].map { |n| n * n } #=> [1, 4, 9]
Array and Rang...
Python memoising/deferred lookup property decorator
Recently I've gone through an existing code base containing many classes where instance attributes reflect values stored in a database. I've refactored a lot of these attributes to have their database lookups be deferred, ie. not be initialised in the constructor but only upon first read. These attr...
Get selected subcommand with argparse
When I use subcommands with python argparse, I can get the selected arguments.
2 Answers
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How do I associate a Vagrant project directory with an existing VirtualBox VM?
Somehow my Vagrant project has disassociated itself from its VirtualBox VM, so that when I vagrant up Vagrant will import the base-box and create a new virtual machine.
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