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classical inheritance vs prototypal inheritance in javascript
...n: The representation of real world things in computer programs.
Theoretically an abstraction is defined as "a general concept formed by extracting common features from specific examples". However for the sake of this explanation we're going to use the aforementioned definition instead.
Now some o...
Purge or recreate a Ruby on Rails database
...o this:
This will reset your database and reload your current schema with all:
rake db:reset db:migrate
This will destroy your db and then create it and then migrate your current schema:
rake db:drop db:create db:migrate
All data will be lost in both scenarios.
...
How to calculate “time ago” in Java?
In Ruby on Rails, there is a feature that allows you to take any Date and print out how "long ago" it was.
30 Answers
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Datatables: Cannot read property 'mData' of undefined
...o went through this link which didn't yield any results. I have included all the prerequisites where I'm parsing data directly into the DOM. Kindly help me to fix this issue.
...
What does the exclamation mark do before the function?
...s just a function declaration. You would need an invocation, foo(), to actually run the function.
Now, when we add the seemingly innocuous exclamation mark: !function foo() {} it turns it into an expression. It is now a function expression.
The ! alone doesn't invoke the function, of course, but w...
Using ls to list directories and their total sizes
...possible to use ls in Unix to list the total size of a sub-directory and all its contents as opposed to the usual 4K that (I assume) is just the directory file itself?
...
Integer to hex string in C++
...(sizeof(your_type)*2)
<< std::hex << your_int;
So finally, I'd suggest such a function:
template< typename T >
std::string int_to_hex( T i )
{
std::stringstream stream;
stream << "0x"
<< std::setfill ('0') << std::setw(sizeof(T)*2)
...
How do I “Add Existing Item” an entire directory structure in Visual Studio?
I have a free standing set of files not affiliated with any C# project at all that reside in a complicated nested directory structure.
...
Visual Studio 2012 Express is suddenly “incompatible with this version of Windows”?
...e same message on Visual Studio 2012 Premium (on PC where Windows 7 re-installed in last month) - the suggested fix was "Update for Microsoft Visual Studio 2012 (KB2781514)" which seems to have fixed it
www.microsoft.com/en-us/download/details.aspx?id=36020
...
Check number of arguments passed to a Bash script
...nd regex matching.
The following example checks if arguments are valid. It allows a single argument or two.
[[ ($# -eq 1 || ($# -eq 2 && $2 == <glob pattern>)) && $1 =~ <regex pattern> ]]
For pure arithmetic expressions, using (( )) to some may still be better, but they ...