Tutorial by Examples: p

Use putAll to put every member of one map into another. Keys already present in the map will have their corresponding values overwritten. Map<String, Integer> numbers = new HashMap<>(); numbers.put("One", 1) numbers.put("Three", 3) Map<String, Integer> othe...

To begin making modifications to the project's data, you have to obtain a local copy of the versioned project. Use the command line svn client or your favorite SVN client (TortoiseSVN, for example). Your local copy of the project is called a working copy in Subversion and you get it by issuing the c...

If you want to get the versioned project's data, but you don't need any of the version control capabilities offered by Subversion, you could run svn export <URL> command. Here is an example: $ svn export https://svn.example.com/svn/MyRepo/MyProject/trunk As a result, you will get the proje...

You are not the only person working on the project, right? This means that your colleagues are also making modifications to the project's data. To stay up to date and to fetch the modifications committed by others, you should run svn update command in your working copy. As a result, your working cop...

If a remote branch has been deleted, your local repository has to be told to prune the reference to it. To prune deleted branches from a specific remote: git fetch [remote-name] --prune To prune deleted branches from all remotes: git fetch --all --prune

A wide variety of standard library functions have among their effects copying byte sequences from one memory region to another. Most of these functions have undefined behavior when the source and destination regions overlap. For example, this ... #include <string.h> /* for memcpy() */ ch...

To uninstall one or more locally installed packages, use: npm uninstall <package name> The uninstall command for npm has five aliases that can also be used: npm remove <package name> npm rm <package name> npm r <package name> npm unlink <package name> npm un ...

A group is a section of a regular expression enclosed in parentheses (). This is commonly called "sub-expression" and serves two purposes: It makes the sub-expression atomic, i.e. it will either match, fail or repeat as a whole. The portion of text it matched is accessible in the remai...

Since Groups are "numbered" some engines also support matching what a group has previously matched again. Assuming you wanted to match something where two equals strings of length three are divided by a $ you'd use: (.{3})\$\1 This would match any of the following strings: "abc$...

Evaluates its first operand, and, if the resulting value is not equal to zero, evaluates its second operand. Otherwise, it evaluates its third operand, as shown in the following example: a = b ? c : d; is equivalent to: if (b) a = c; else a = d; This pseudo-code represents it : c...

Evaluates its left operand, discards the resulting value, and then evaluates its rights operand and result yields the value of its rightmost operand. int x = 42, y = 42; printf("%i\n", (x *= 2, y)); /* Outputs "42". */ The comma operator introduces a sequence point between i...

This example shows how to match an input against several values: def f(x: Int): String = x match { case 1 => "One" case 2 => "Two" case _ => "Unknown!" } f(2) // "Two" f(3) // "Unknown!" Live demo Note: _ is the fall th...

In standard pattern matching, the identifier used will shadow any identifier in the enclosing scope. Sometimes it is necessary to match on the enclosing scope's variable. The following example function takes a character and a list of tuples and returns a new list of tuples. If the character existed...

This example shows the usage of the ILGenerator by generating code that makes use of already existing and new created members as well as basic Exception handling. The following code emits a DynamicAssembly that contains an equivalent to this c# code: public static class UnixTimeHelper { priva...

Branching in Subversion is very simple. In the simplest form, creating a new branch requires you to run the command against the remote repository's URLs. For example, let's create a new branch out of the mainline trunk: svn copy https://svn.example.com/svn/MyRepo/MyProject/trunk https://svn.example...

When you interact with the remote central repository using your private local workspace -- the working copy -- you can use repository-relative URL instead of direct URL to URL copy to create a new branch: svn copy "^/MyProject/trunk" "^/MyProject/branches/MyNewBranch" -m "C...

The working copy (WC) is your local and private workspace that you use to interact with the central Subversion repository. You use the working copy to modify the contents of your project and fetch changes committed by others. The working copy contains your project's data and looks and acts like a r...

for (x <- 1 to 10) println("Iteration number " + x) This demonstrates iterating a variable, x, from 1 to 10 and doing something with that value. The return type of this for comprehension is Unit.

This demonstrates a filter on a for-loop, and the use of yield to create a 'sequence comprehension': for ( x <- 1 to 10 if x % 2 == 0) yield x The output for this is: scala.collection.immutable.IndexedSeq[Int] = Vector(2, 4, 6, 8, 10) A for comprehension is useful when you need to crea...

This shows how you can iterate over multiple variables: for { x <- 1 to 2 y <- 'a' to 'd' } println("(" + x + "," + y + ")") (Note that to here is an infix operator method that returns an inclusive range. See the definition here.) This creates the outp...