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proc myproc {alpha beta} { ... set foo $alpha set beta $bar ;# note: possibly useless invocation } myproc 12 34 ;# alpha will be 12, beta will be 34 If the argument list consists of words, those will be the names of local variables in the procedure, and their initi...

### Definition proc myproc {alpha {beta {}} {gamma green}} { puts [list $alpha $beta $gamma] } ### Use myproc A # => A {} green myproc A B # => A B green myproc A B C # => A B C This procedure accepts one, two, or three arguments: those parameters whose names are the fi...

proc myproc args { ... } proc myproc {args} { ... } ;# equivalent If the special parameter name args is the last item in the argument list, it receives a list of all arguments at that point in the command line. If there are none, the list is empty. There can be arguments, including optional one...

proc myproc {varName alpha beta} { upvar 1 $varName var set var [expr {$var * $alpha + $beta}] } set foo 1 myproc foo 10 5 puts $foo # => 15 In this particular case, the procedure is given the name of a variable in the current scope. Inside a Tcl procedure, such variables aren't...

Variables in Visual Basic are declared using the Dim keyword. For example, this declares a new variable called counter with the data type Integer: Dim counter As Integer A variable declaration can also include an access modifier, such as Public, Protected, Friend, or Private. This works in conju...

# application.rb config.time_zone = 'Eastern Time (US & Canada)'

# application.rb config.time_zone = 'Eastern Time (US & Canada)' config.active_record.default_timezone = :local

Switch syntax highlighting on, when the terminal has colors if &t_Co > 2 || has("gui_running") syntax on end Show trailing whitespace and tabs. Showing tabs can be especially useful when looking for errors in Makefiles. set list listchars=tab:\|_,trail:. highlight Specia...

When a tabular form is posted, the items in each record are available to PL/SQL code via the "APEX_APPLICATION.G_Fnn" arrays. G_F01 corresponds to the first editable column, G_F02 to the 2nd, and so on. For example, you can loop through each record and access the posted values for each fie...

Every Time you create an anonymous class, it retains an implicit reference to its parent class. So when you write: public class LeakyActivity extends Activity { ... foo.registerCallback(new BarCallback() { @Override public void onBar() { ...

Often you will want to wrap some of Android's classes in easier to use utility classes. Those utility classes often require a context to access the android OS or your apps' resources. A common example of this is a wrapper for the SharedPreferences class. In order to access Androids shared preference...

This is the code for changing output application file name (.apk). The name can be configured by assigning a different value to newName android { applicationVariants.all { variant -> def newName = "ApkName"; variant.outputs.each { output -> def ...

If you are optimizing all images manually, disable APT Cruncher for a smaller APK file size. android { aaptOptions { cruncherEnabled = false } }

synchronized is a low-level concurrency construct that can help preventing multiple threads access the same resources. Introduction for the JVM using the Java language. anInstance.synchronized { // code to run when the intristic lock on `anInstance` is acquired // other thread cannot enter co...

The GetParentFolderName method returns the parent folder for any path. While this can also be used with folders, it is arguably more useful for extracting the path from an absolute file path: Dim fso As New Scripting.FileSystemObject Debug.Print fso.GetParentFolderName("C:\Users\Me\My Docume...

In some cases it is necessary to calculate a variable amount of values on separate Futures. Assume to have a List[Future[Int]], but instead a List[Int] needs to be processed. Then the question is how to turn this instance of List[Future[Int]] into a Future[List[Int]]. For this purpose there is the s...

Creating a namedtuple with type hints is done using the function NamedTuple from the typing module: import typing Point = typing.NamedTuple('Point', [('x', int), ('y', int)]) Note that the name of the resulting type is the first argument to the function, but it should be assigned to a variable ...

Keeping a GUI responsive while running a lengthy process requires either some very elaborate "callbacks" to allow the GUI to process its message queue, or the use of (background) (worker) threads. Kicking off any number of threads to do some work usually isn't a problem. The fun starts wh...

Start with importing the library. from amqpstorm import Connection When consuming messages, we first need to define a function to handle the incoming messages. This can be any callable function, and has to take a message object, or a message tuple (depending on the to_tuple parameter defined in ...

Start with importing the library. from amqpstorm import Connection from amqpstorm import Message Next we need to open a connection to the RabbitMQ server. connection = Connection('127.0.0.1', 'guest', 'guest') After that we need to set up a channel. Each connection can have multiple channel...