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>>> expression = '5 + 3 * a' >>> a = 5 >>> result = eval(expression) >>> result 20

compile built-in function can be used to precompile an expression to a code object; this code object can then be passed to eval. This will speed up the repeated executions of the evaluated code. The 3rd parameter to compile needs to be the string 'eval'. >>> code = compile('a * b + c', '&l...

>>> variables = {'a': 6, 'b': 7} >>> eval('a * b', globals=variables) 42 As a plus, with this the code cannot accidentally refer to the names defined outside: >>> eval('variables') {'a': 6, 'b': 7} >>> eval('variables', globals=variables) Traceback (most ...

You can also use regular expressions to split a string. For example, import re data = re.split(r'\s+', 'James 94 Samantha 417 Scarlett 74') print( data ) # Output: ['James', '94', 'Samantha', '417', 'Scarlett', '74']

If you have a vsix file, you can install it by running the file. Get the vsix file (this is the extension installer) Run the file. In the window that opens, confirm the installation.

In Visual studio go to Tools > Extensions and updates... In the window that opens go to online Select Visual Studio Gallery You can search for an extension on the search box at the upper right corner Select the extension you want to add Click on download. Once download is complete, click...

It is not possible to use eval or exec to execute code from untrusted user securely. Even ast.literal_eval is prone to crashes in the parser. It is sometimes possible to guard against malicious code execution, but it doesn't exclude the possibility of outright crashes in the parser or the tokenizer....

<div class="navbar navbar-inverse navbar-fixed-top"> <div class="container"> <div class="navbar-header"> <!--- vvv Hamburger icon that gets shown when window reaches a certain scale vvv ---> <button type...

In Scala operators (such as +, -, *, ++, etc.) are just methods. For instance, 1 + 2 can be written as 1.+(2). These sorts of methods are called 'infix operators'. This means custom methods can be defined on your own types, reusing these operators: class Matrix(rows: Int, cols: Int, val data: Seq[...

Following code will release the lock. There will be no problem. Behind the scenes lock statement works as try finally lock(locker) { throw new Exception(); } More can be seen in the C# 5.0 Specification: A lock statement of the form lock (x) ... where x is an expression of a referenc...

This example will show you how to create a simple animation using the canvas and the 2D context. It is assumed you know how to create and add a canvas to the DOM and obtain the context // this example assumes ctx and canvas have been created const textToDisplay = "This is an example that uses...

Commands have one input (STDIN) and two kinds of outputs, standard output (STDOUT) and standard error (STDERR). For example: STDIN root@server~# read Type some text here Standard input is used to provide input to a program. (Here we're using the read builtin to read a line from STDIN.) STDO...

Other examples couldn't clearly explain to me how to trigger the conditional logic. This example also shows that underlying commands will also listen to the -Confirm flag! <# Restart-Win32Computer #> function Restart-Win32Computer { [CmdletBinding(SupportsShouldProcess=$true,Conf...

Schedulers are an RxJava abstraction about processing unit. A scheduler can be backed by a Executor service, but you can implement your own scheduler implementation. A Scheduler should meet this requirement : Should process undelayed task sequencially (FIFO order) Task can be delayed A Sched...

Clojure uses prefix notation, that is: The operator comes before its operands. For example, a simple sum of two numbers would be: (+ 1 2) ;; => 3 Macros allow you to manipulate the Clojure language to a certain degree. For example, you could implement a macro that let you write code in infi...

Suppose we have an interface: interface IPerson { name: string; age: number; breath(): void; } And we want to create more specific interface that has the same properties of the person, we can do it using the extends keyword: interface IManager extends IPerson { managerId:...

An example XML file <Sample> <Account> <One number="12"/> <Two number="14"/> </Account> <Account> <One number="14"/> <Two number="16"/> </Account&gt...

An explicit intent is used for starting an activity or service within the same application package. In this case the name of the intended class is explicitly mentioned: Intent intent = new Intent(this, MyComponent.class); startActivity(intent); However, an implicit intent is sent across the sys...

functions.php: // We add the action twice, once for logged in users and once for non logged in users. add_action( 'wp_ajax_my_action', 'my_action_callback' ); add_action( 'wp_ajax_nopriv_my_action', 'my_action_callback' ); // Enqueue the script on the front end. add_action( 'wp_enqueue_script...

You can create a UIColor from a hexadecimal number or string, e.g. 0xff00cc, "#FFFFFF" Swift Int Value extension UIColor { convenience init(hex: Int, alpha: CGFloat = 1.0) { let r = CGFloat((hex >> 16) & 0xff) / 255 let g = CGFloat((hex >> 08) &amp...