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Mediator Vs Observer Object-Oriented Design Patterns
...ave been reading the Gang Of Four , in order to solve some of my problems and came across the Mediator pattern.
8 Answer...
Fastest hash for non-cryptographic uses?
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CRC32 is pretty fast and there's a function for it: http://www.php.net/manual/en/function.crc32.php
But you should be aware that CRC32 will have more collisions than MD5 or even SHA-1 hashes, simply because of the reduced length (32 bits compare...
Rails: Using build with a has_one association in rails
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The build method signature is different for has_one and has_many associations.
class User < ActiveRecord::Base
has_one :profile
has_many :messages
end
The build syntax for has_many association:
user.messages.build
The build syntax for has_one association:
user.bu...
Choosing the default value of an Enum type without having to change values
...he values? The numbers required might be set in stone for whatever reason, and it'd be handy to still have control over the default.
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Is there replacement for cat on Windows
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Windows type command works similarly to UNIX cat.
Example 1:
type file1 file2 > file3
is equivalent of:
cat file1 file2 > file3
Example 2:
type *.vcf > all_in_one.vcf
This command will merge all the vcards into one.
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Better to 'try' something and catch the exception or test if it's possible first to avoid an excepti
Should I test if something is valid or just try to do it and catch the exception?
8 Answers
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Error installing mysql2: Failed to build gem native extension
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On Ubuntu/Debian and other distributions using aptitude:
sudo apt-get install libmysql-ruby libmysqlclient-dev
Package libmysql-ruby has been phased out and replaced by ruby-mysql. This is where I found the solution.
If the above command ...
How do I merge a specific commit from one branch into another in Git?
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The git cherry-pick <commit> command allows you to take a single commit (from whatever branch) and, essentially, rebase it in your working branch.
Chapter 5 of the Pro Git book explains it better than I can, complete with diagrams and such. (The chapter on ...
How to bind multiple values to a single WPF TextBlock?
... </TextBlock.Text>
</TextBlock>
Giving Name a value of Foo and ID a value of 1, your output in the TextBlock would then be Foo + 1.
Note: that this is only supported in .NET 3.5 SP1 and 3.0 SP2 or later.
sha...
What requirement was the tuple designed to solve?
...urn, or when you want to key a dictionary off of two data rather than one, and so on.
Languages like F# which support tuple types natively provide a great deal of flexibility to their users; they are an extremely useful set of data types. The BCL team decided to work with the F# team to standardi...