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What is an “unwrapped value” in Swift?
...st, you have to understand what an Optional type is. An optional type basically means that the variable can be nil.
Example:
var canBeNil : Int? = 4
canBeNil = nil
The question mark indicates the fact that canBeNil can be nil.
This would not work:
var cantBeNil : Int = 4
cantBeNil = nil // can...
Should enums in C# have their own file? [closed]
..." (how much does an extra file cost?), but it is often inconventient. Usually there's one class that's most closely associtated with the enum, and I put them in the same file.
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Are the days of passing const std::string & as a parameter over?
...he said is because of cases like this.
Let's say I have function A which calls function B, which calls function C. And A passes a string through B and into C. A does not know or care about C; all A knows about is B. That is, C is an implementation detail of B.
Let's say that A is defined as follow...
IntelliJ and Tomcat.. Howto..?
...ites with Tomcat as the local server to manage it.
In Netbeans it was "Install, write hit Run and it works"
How do I pull the same thing off in IntelliJ?
...
Similar to jQuery .closest() but traversing descendants?
...found.length) break; // At least one match: break loop
// Get all children of the current set
$currentSet = $currentSet.children();
}
return $found.first(); // Return first match of the collection
}
})(jQuery);
...
How to succinctly write a formula with many variables from a data frame?
...
There is a special identifier that one can use in a formula to mean all the variables, it is the . identifier.
y <- c(1,4,6)
d <- data.frame(y = y, x1 = c(4,-1,3), x2 = c(3,9,8), x3 = c(4,-4,-2))
mod <- lm(y ~ ., data = d)
You can also do things like this, to use all variables but...
Something better than .NET Reflector? [closed]
...y, but ever since Red Gate Software took over it has gone downhill dramatically. Now it forces me to update (which is absolutely ridiculous), half the time the update doesn't go smoothly, and it is increasingly hindering my productivity with each update. I am sick of it, and I am ready for something...
How can I mix LaTeX in with Markdown? [closed]
...s LaTeX processor with the command: pandoc -s -i Hello.md -o Hello.pdf
Finally, there are some open source LaTeX templates like this one: https://github.com/Wandmalfarbe/pandoc-latex-template, that can be used for better formatting.
As always, the reader should dig deeper if he has less trivial use...
Move existing, uncommitted work to a new branch in Git
...ve your current branch as it is, create and checkout a new branch and keep all your changes. You can then stage changes in files to commit with:
git add <files>
and commit to your new branch with:
git commit -m "<Brief description of this commit>"
The changes in the working direct...
java.util.Date vs java.sql.Date
...ns, you've hit my favorite pet peeve with JDBC: Date class handling.
Basically databases usually support at least three forms of datetime fields which are date, time and timestamp. Each of these have a corresponding class in JDBC and each of them extend java.util.Date. Quick semantics of each of th...