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4 min readIn Kotlin, you can avoid writing the same null check multiple times by using the safe call operator (?.) or the Elvis operator (?:).The safe call operator (?.) allows you to access properties or call methods on an object only if the object is not null. If the object is null, the expression returns null instead of throwing a NullPointerException.For example: val length = str?.length The Elvis operator (?:) is used to provide a default value in case the expression on the left is null.
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5 min readIn Elixir, you can use the Regex.scan/3 function to find words matching a regular expression. This function takes in a string, a regular expression pattern, and options. It returns a list of all matches found in the string.Here's an example of how you can use Regex.scan/3 to find words in a string: string = "Hello World" pattern = ~r/\w+/ matches = Regex.scan(pattern, string) IO.
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5 min readIn Kotlin, you can reference a property from a different class by using dot notation. If the property is public, you can simply write the class name followed by a dot and then the property name. If the property is private, you will need to create a getter method in the class containing the property and then use that method to access the property from another class.
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7 min readTo make user-friendly URLs with .htaccess and PHP, you will need to first create a .htaccess file in the root directory of your website. In this file, you can use Apache's mod_rewrite module to rewrite URLs in a more readable format.Next, you will need to set up rules in the .htaccess file to redirect URLs to a PHP script that will handle the request. This script will then parse the URL and route the request to the appropriate page or function.
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5 min readTo fetch elixir dependencies per environment, you can use Mix environments. Mix allows you to define different environments such as :dev, :test, and :prod. Each environment can have its own configuration and dependencies.You can define dependencies specific to each environment by using the env key in your mix.exs file. For example, you can define {:dependency, "~> x.x.x", env: :test} to include a dependency only in the test environment.
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4 min readIn Kotlin, you can iterate over a collection of items and access the next item in the collection by using the windowed function. This function allows you to specify the size of the sliding window and a step parameter to control how many items to move on each iteration. By utilizing the windowed function, you can easily access the current item and the next item in the collection within the loop body.
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3 min readTo map all requests to a subdirectory using .htaccess, you can add the following code to your .htaccess file:RewriteEngine On RewriteBase / RewriteRule ^(.*)$ subdirectory/$1 [L]This code will redirect any request made to the root directory to the subdirectory specified. This way, all requests will be mapped to the desired subdirectory without changing the URLs in the browser.Make sure to replace "subdirectory" with the actual name of the subdirectory you want to map all requests to.
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5 min readThe .htaccess file should be placed inside the directory where your CGI scripts are located, typically the cgi-bin directory. This file contains configurations that can override the server's global settings for that specific directory. Make sure the directory has the necessary permissions to allow the .htaccess file to be read by the server. Additionally, verify that the Apache server is configured to allow the use of .htaccess files.
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4 min readThe =~ operator in Elixir is a pattern match operator that is used to match a value against a pattern. It is similar to the case statement, but it is more concise and convenient for simple matching of values. The syntax for using the =~ operator is as follows:value =~ patternIf the value matches the pattern, the operator returns true, otherwise it returns false.
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5 min readTo write a generic type serializer in Kotlin, you can start by creating a generic class that takes the type of object you want to serialize as a parameter. Within this class, you can define a function that will handle the serialization logic for objects of that type.You can use reflection to access the properties of the object and serialize them into a suitable format, such as JSON or XML.
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3 min readTo create a .htaccess file for PHP, you can use a text editor such as Notepad or TextEdit. Start by opening the text editor and creating a new file. Save the file as ".htaccess" (make sure the file extension is .htaccess and not .txt).You can then add various configurations to the .htaccess file to customize the behavior of your PHP scripts. For example, you can set up redirections, protect directories with a password, enable server-side caching, and more.Remember to test your .