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Error installing mysql2: Failed to build gem native extension
...with-mysql-include="c:\Program Files\MySQL\MySQL Server 5.5\include"'
Now the gem should have installed correctly
Lastly copy the libmysql.dll file from
C:\Program Files\MySQL\MySQL Server 5.5\lib
to
C:\Rails\Ruby1.9.2\bin
--- Install the mysql2 Gem ---
You will now be able to u...
Installing vim with ruby support (+ruby)
...
I think "Compiling Vim With Ruby Integration On Snow Leopard" might actually help. I'm on exactly same boat at the moment.
Ok... got it to work. Took me like half hour or so.
This should help (I got Ubuntu):
sudo apt-get install mercurial
hg clone https://vim.googlecod...
Convert a list to a data frame
...
Update July 2020:
The default for the parameter stringsAsFactors is now default.stringsAsFactors() which in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns...
What is the curiously recurring template pattern (CRTP)?
...ss A : public X<A> {...};
It is curiously recurring, isn't it? :)
Now, what does this give you? This actually gives the X template the ability to be a base class for its specializations.
For example, you could make a generic singleton class (simplified version) like this
template <cl...
How to detect if multiple keys are pressed at once using JavaScript?
...
Note: keyCode is now deprecated.
Multiple keystroke detection is easy if you understand the concept
The way I do it is like this:
var map = {}; // You could also use an array
onkeydown = onkeyup = function(e){
e = e || event; // to deal w...
Difference between Covariance & Contra-variance
...s T → IE<T>. Notice that this is a "thin arrow".
With me so far?
Now let's consider a relation. There is an assignment compatibility relationship between pairs of types in the first set. A value of type Tiger can be assigned to a variable of type Animal, so these types are said to be "assi...
What is event bubbling and capturing?
...
useCapture now supported in IE >= 9. source
– beatgammit
Aug 20 '13 at 17:10
...
Unable to open project… cannot be opened because the project file cannot be parsed
...jectname.xcodeproj file here projectname will be the name of your project. Now after right clicked select Show Packages Contents. After that open your projectname.pbxproj file in a text editor. Now search for the line containing <<<<<<< .mine, ======= and >>>>>>...
How to download source in ZIP format from GitHub?
...
not without using the Github API as far as I know.
– Christoph
Feb 11 '13 at 15:25
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How many and which are the uses of “const” in C++?
...ect remain the same. Once one of the object changes data, you however need now two versions: One for the original, and one for the copy. That is, you copy on a write to either object, so that they now both have their own version.
Using code:
int main() {
string const a = "1234";
string co...