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Lazy, or irrefutable, patterns (denoted with the syntax ~pat) are patterns that always match, without even looking at the matched value. This means lazy patterns will match even bottom values. However, subsequent uses of variables bound in sub-patterns of an irrefutable pattern will force the patter...

CLISP has an integration with GNU Readline. For improvements for other implementations see: How to customize the SBCL REPL.

Most Common Lisp implementations will try to load an init file on startup: ImplementationInit fileSite/System Init fileABCL$HOME/.abclrcAllegro CL$HOME/.clinit.clECL$HOME/.eclrcClasp$HOME/.clasprcCLISP$HOME/.clisprc.lispClozure CLhome:ccl-init.lisp or home:ccl-init.fasl or home:.ccl-init.lispCMUCL$...

Common Lisp has a way to influence the compilation strategies. It makes sense to define your preferred values. Optimization values are between 0 (unimportant) and 3 (extremely important). 1 is the neutral value. It's useful to always use safe code (safety = 3) with all runtime checks enabled. Not...

Rust's coherence rule requires that either the trait or the type for which you are implementing the trait must be defined in the same crate as the impl, so it is not possible to implement Serialize and Deserialize for a type in a different crate directly. The newtype pattern and Deref coercion provi...

Use vectors to calculate incremental [x,y] from [startX,startY] to [endX,endY] // dx is the total distance to move in the X direction var dx = endX - startX; // dy is the total distance to move in the Y direction var dy = endY - startY; // use a pct (percentage) to travel the total distance...

With functional testing data is often modified. This can cause subsequent runs of the test suite to fail (as the data could have changed from the original state it was in). If you have setup your data source using an ORM or framework that supports migration or seeding (like Doctrine, Propel, Larave...

Because data is sensitive when dealt with between two threads (think concurrent read and concurrent write can conflict with one another, causing race conditions), a set of unique objects were made in order to facilitate the passing of data back and forth between threads. Any truly atomic operation c...

Detailed instructions on getting filemaker set up or installed.

PHP is able to parse a number of date formats. If you want to parse a non-standard format, or if you want your code to explicitly state the format to be used, then you can use the static DateTime::createFromFormat method: Object oriented style $format = "Y,m,d"; $time = "2009,2,26&...

Utilizing .Net System.Security.Cryptography.HashAlgorithm namespace to generate the message hash code with the algorithms supported. $example="Nobody expects the Spanish Inquisition." #calculate $hash=[System.Security.Cryptography.HashAlgorithm]::Create("sha256").ComputeHas...

Data providers allow creating multiple test inputs to be run within a test. Let's consider a test which verifies that numbers are doubled correctly. To create data provider provide a static method which returns either Object[][] or Iterator<Object[]> (the latter allows for lazy computation of ...

zsh loads configuration from the ~/.zshrc file on startup. If you make changes to that file, you can either restart zsh or run the following command to reload the configuration. . ~/.zshrc You can alias this useful command in your ~/.zshrc like this: alias reload=". ~/.zshrc"

Detailed instructions on getting yarn set up or installed. If you have npm installed on your system: npm install --global yarn On macOS: via Homebrew: brew install yarn via MacPorts: sudo port install yarn (node will be installed if not present) On Windows: via Chocolatey: choco install...

mod_rewrite must be enabled before being used on an Apache server. Debian/Ubuntu Run a2enmod rewrite Then restart Apache with service apache2 restart General case Add or uncomment the following line in the static configuration file (such as httpd.conf): LoadModule rewrite_module modules/mod_re...

Entity class @Entity @Table(name = "USER") public class User { @Id @Column(name = "ID") private Long id; @Column(name = "USERNAME") private String username; @ManyToOne @JoinColumn("ORGANIZATION_ID") pr...

PHP 4+ supplies a method, format that converts a DateTime object into a string with a desired format. According to PHP Manual, this is the object oriented function: public string DateTime::format ( string $format ) The function date() takes one parameters - a format, which is a string Format T...

Consider these two micro-benchmarks: The first benchmark simply creates, starts and joins threads. The thread's Runnable does no work. public class ThreadTest { public static void main(String[] args) throws Exception { while (true) { long start = System.nanoTime(); ...

If you need to store images or videos in the column then we need to change the value as needed by your application max_allowed_packet = 10M M is Mb, G in Gb, K in Kb

Conditions can also be expressions: $myInput = 0 switch($myInput) { # because the result of the expression, 4, # does not equal our input this block should not be run. (2+2) { 'True. 2 +2 = 4' } # because the result of the expression, 0, # does equal our input this ...