Search results
Results From The WOW.Com Content Network
Thus, declaring const string testUserName = "John" is better than several occurrences of the 'magic value' "John" in a test suite. For example, if it is required to randomly shuffle the values in an array representing a standard pack of playing cards, this pseudocode does the job using the Fisher–Yates shuffle algorithm:
In other languages, variables are often initialized to known values when created. Examples include: VHDL initializes all standard variables into special 'U' value. It is used in simulation, for debugging, to let the user to know when the don't care initial values, through the multi-valued logic, affect the output.
Perl autovivification can be contrasted against languages such as Python, PHP, Ruby, and many of the C style languages, where dereferencing null or undefined values is not generally permitted. [ a ] It can be compared to the HTML standard's "named access on the window object" [ 2 ] which results in corresponding globally scoped variables being ...
Taint checking is a feature in some computer programming languages, such as Perl, [1] Ruby [2] or Ballerina [3] designed to increase security by preventing malicious users from executing commands on a host computer.
In these languages, including the line __DATA__ (Perl) or __END__ (Ruby, old Perl) marks the end of the code segment and the start of the data segment. Only the contents prior to this line are executed, and the contents of the source file after this line are available as a file object: PACKAGE::DATA in Perl (e.g., main::DATA) and DATA in Ruby.
This includes Perl itself, nearly all publicly released modules, many scripts, most design documents, many articles on Perl.com and other Perl-related web sites, and the Parrot virtual machine. Pod is rarely read in the raw, although it is designed to be readable without the assistance of a formatting tool.
Hexspeak is a novelty form of variant English spelling using the hexadecimal digits. Created by programmers as memorable magic numbers, hexspeak words can serve as a clear and unique identifier with which to mark memory or data.
An undefined value must not be confused with empty string, Boolean "false" or other "empty" (but defined) values. Depending on circumstances, evaluation to an undefined value may lead to exception or undefined behaviour, but in some programming languages undefined values can occur during a normal, predictable course of program execution.