Perl Modules
A Perl module is a discrete component of software for the Perl programming language. Technically, it is a particular set of conventions for using Perl's package mechanism that has become universally adopted. A module defines its source code to be in a ''package'' (much like a Java package), the Perl mechanism for defining namespaces, e.g. ''CGI'' or ''Net::FTP'' or ''XML::Parser''; the file structure mirrors the namespace structure (e.g. the source code for ''Net::FTP'' is in ''Net/FTP.pm''). Furthermore, a module is the Perl equivalent of the class when object-oriented programming is employed. A collection of modules, with accompanying documentation, build scripts, and usually a test suite, composes a distribution. The Perl community has a sizable library of distributions available for search and download via CPAN. Perl is a language allowing many different styles of programming. A developer is as likely to find a module written in a procedural style (for exampleTest::Sim ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Software
Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work. At the lowest programming level, executable code consists of machine language instructions supported by an individual processor—typically a central processing unit (CPU) or a graphics processing unit (GPU). Machine language consists of groups of binary values signifying processor instructions that change the state of the computer from its preceding state. For example, an instruction may change the value stored in a particular storage location in the computer—an effect that is not directly observable to the user. An instruction may also invoke one of many input or output operations, for example displaying some text on a computer screen; causing state changes which should be visible to the user. The processor executes the instructions in the order they are provided, unless it is instructed ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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CPAN
The Comprehensive Perl Archive Network (CPAN) is a repository of over 250,000 software modules and accompanying documentation for 39,000 distributions, written in the Perl programming language by over 12,000 contributors. ''CPAN'' can denote either the archive network or the Perl program that acts as an interface to the network and as an automated software installer (somewhat like a package manager). Most software on CPAN is free and open source software. History CPAN was conceived in 1993 and has been active online since October 1995. It is based on the CTAN model and began as a place to unify the structure of scattered Perl archives. Role Like many programming languages, Perl has mechanisms to use external libraries of code, making one file contain common routines used by several programs. Perl calls these ''modules''. Perl modules are typically installed in one of several directories whose paths are placed in the Perl interpreter when it is first compiled; on Unix-like ope ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Sigil (computer Programming)
In computer programming, a sigil () is a symbol affixed to a variable name, showing the variable's datatype or scope, usually a prefix, as in $foo, where $ is the sigil. ''Sigil'', from the Latin '' sigillum'', meaning a "little sign", means ''a sign or image supposedly having magical power''. Sigils can be used to separate and demarcate namespaces that possess different properties or behaviors. Historical context The use of sigils was popularized by the BASIC programming language. The best known example of a sigil in BASIC is the dollar sign ("$") appended to the names of all strings. Many BASIC dialects use other sigils (like "%") to denote integers and floating point numbers and their precision, and sometimes other types as well. Larry Wall adopted shell scripting's use of sigils for his Perl, Perl programming language. In Perl, the sigils do not specify fine-grained data-types like strings and integers, but the more general categories of scalar (computing), scalars (using ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Hello World Program
''Hello'' is a salutation or greeting in the English language. It is first attested in writing from 1826. Early uses ''Hello'', with that spelling, was used in publications in the U.S. as early as the 18 October 1826 edition of the ''Norwich Courier'' of Norwich, Connecticut. Another early use was an 1833 American book called ''The Sketches and Eccentricities of Col. David Crockett, of West Tennessee'', which was reprinted that same year in '' The London Literary Gazette''. The word was extensively used in literature by the 1860s. Etymology According to the ''Oxford English Dictionary'', ''hello'' is an alteration of ''hallo'', ''hollo'', which came from Old High German "''halâ'', ''holâ'', emphatic imperative of ''halôn'', ''holôn'' to fetch, used especially in hailing a ferryman". It also connects the development of ''hello'' to the influence of an earlier form, ''holla'', whose origin is in the French ''holà'' (roughly, 'whoa there!', from French ''là'' 'there'). As i ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Manual Page (Unix)
A man page (short for manual page) is a form of software documentation usually found on a Unix or Unix-like operating system. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts. A user may invoke a man page by issuing the man command. By default, man typically uses a terminal pager program such as more or less to display its output. Man pages are often referred to as an ''on-line'' or ''online'' form of software documentation, * even though the man command does not require internet access, dating back to the times when printed ''out-of-band'' manuals were the norm. History In the first two years of the history of Unix, no documentation existed. The Unix Programmer's Manual' was first published on November 3, 1971. The first actual man pages were written by Dennis Ritchie and Ken Thompson at the insistence of their manager Doug McIlroy in 1971. Aside from the man pages, the ''Programmer' ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Java (programming Language)
Java is a high-level, class-based, object-oriented programming language that is designed to have as few implementation dependencies as possible. It is a general-purpose programming language intended to let programmers ''write once, run anywhere'' ( WORA), meaning that compiled Java code can run on all platforms that support Java without the need to recompile. Java applications are typically compiled to bytecode that can run on any Java virtual machine (JVM) regardless of the underlying computer architecture. The syntax of Java is similar to C and C++, but has fewer low-level facilities than either of them. The Java runtime provides dynamic capabilities (such as reflection and runtime code modification) that are typically not available in traditional compiled languages. , Java was one of the most popular programming languages in use according to GitHub, particularly for client–server web applications, with a reported 9 million developers. Java was originally developed ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Javadoc
Javadoc (originally cased JavaDoc) is a documentation generator created by Sun Microsystems for the Java language (now owned by Oracle Corporation) for generating API documentation in HTML format from Java source code. The HTML format is used for adding the convenience of being able to hyperlink related documents together. The "doc comments" format used by Javadoc is the de facto industry standard for documenting Java classes. Some IDEs, like IntelliJ IDEA, NetBeans and Eclipse, automatically generate Javadoc templates. Many file editors assist the user in producing Javadoc source and use the Javadoc info as internal references for the programmer. Javadoc also provides an API for creating doclets and taglets, which allows users to analyze the structure of a Java application. This is how JDiff can generate reports of what changed between two versions of an API. Javadoc does not affect performance in Java as all comments are removed at compilation time. Writing comments and Javado ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Plain Old Documentation
Plain Old Documentation (pod) is a lightweight markup language used to document the Perl programming language as well as Perl modules and programs. Design Pod is designed to be a simple, clean language with just enough syntax to be useful. It purposefully does not include mechanisms for fonts, images, colors or tables. Some of its goals are: * Easy to parse * Easy to convert to other formats, such as XML, TeX or Markdown * Easy to incorporate sample code * Easy to read without a pod formatter (i.e. in its source-code form) * Easy to write in An extended version of pod that supports tables and footnotes called PseudoPOD has been used by O'Reilly & Associates to produce several Perl books, most notably ''Programming Perl'' by Larry Wall, Tom Christiansen, and Jon Orwant. Pod makes it easy to write manual pages, which are well suited to user-oriented documents. In contrast, other documentation systems, such as Python's Docstring or Java's Javadoc, though they can be used for user ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Scope (programming)
In computer programming, the scope of a name binding (an association of a name to an entity, such as a variable) is the part of a program where the name binding is valid; that is, where the name can be used to refer to the entity. In other parts of the program, the name may refer to a different entity (it may have a different binding), or to nothing at all (it may be unbound). Scope helps prevent name collisions by allowing the same name to refer to different objects – as long as the names have separate scopes. The scope of a name binding is also known as the visibility of an entity, particularly in older or more technical literature—this is from the perspective of the referenced entity, not the referencing name. The term "scope" is also used to refer to the set of ''all'' name bindings that are valid within a part of a program or at a given point in a program, which is more correctly referred to as ''context'' or ''environment''. Strictly speaking and in practice for most pro ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Compiler Directive
In computer programming, a directive or pragma (from "pragmatic") is a language construct that specifies how a compiler (or other translator) should process its input. Directives are not part of the grammar of a programming language, and may vary from compiler to compiler. They can be processed by a preprocessor to specify compiler behavior, or function as a form of in-band parameterization. In some cases directives specify global behavior, while in other cases they only affect a local section, such as a block of programming code. In some cases, such as some C programs, directives are optional compiler hints, and may be ignored, but normally they are prescriptive, and must be followed. However, a directive does not perform any action in the language itself, but rather only a change in the behavior of the compiler. This term could be used to refer to proprietary third party tags and commands (or markup) embedded in code that result in additional executable processing that extend t ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mixin
In object-oriented programming languages, a mixin (or mix-in) is a class that contains methods for use by other classes without having to be the parent class of those other classes. How those other classes gain access to the mixin's methods depends on the language. Mixins are sometimes described as being "included" rather than "inherited". Mixins encourage code reuse and can be used to avoid the inheritance ambiguity that multiple inheritance can cause (the "diamond problem"), or to work around lack of support for multiple inheritance in a language. A mixin can also be viewed as an interface with implemented methods. This pattern is an example of enforcing the dependency inversion principle. History Mixins first appeared in Symbolics's object-oriented Flavors system (developed by Howard Cannon), which was an approach to object-orientation used in Lisp Machine Lisp. The name was inspired by Steve's Ice Cream Parlor in Somerville, Massachusetts: The owner of the ice cream shop of ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Object-oriented
Object-oriented programming (OOP) is a programming paradigm based on the concept of "objects", which can contain data and code. The data is in the form of fields (often known as attributes or ''properties''), and the code is in the form of procedures (often known as ''methods''). A common feature of objects is that procedures (or methods) are attached to them and can access and modify the object's data fields. In this brand of OOP, there is usually a special name such as or used to refer to the current object. In OOP, computer programs are designed by making them out of objects that interact with one another. OOP languages are diverse, but the most popular ones are class-based, meaning that objects are instances of classes, which also determine their types. Many of the most widely used programming languages (such as C++, Java, Python, etc.) are multi-paradigm and they support object-oriented programming to a greater or lesser degree, typically in combination with impera ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |