Perl - Wikipedia. Not to be confused with Pearl. Perl. Paradigmmulti- paradigm: functional, imperative, object- oriented (class- based), reflective, procedural, event- driven, generic. Designed by. Larry Wall. Developer. Larry Wall. First appeared. December 1. Stable release. 5. January 1. 4, 2. 01. The languages in this family include Perl 5 and Perl 6. Perl 6, which began as a redesign of Perl 5 in 2. Both languages continue to be developed independently by different development teams and liberally borrow ideas from one another. The Perl languages borrow features from other programming languages including C, shell script (sh), AWK, and sed. Perl 5 gained widespread popularity in the late 1. CGI scripting language, in part due to its (then) unsurpassed. It has been nicknamed . Perl 3, released in 1. Originally, the only documentation for Perl was a single (increasingly lengthy) man page. In 1. 99. 1, Programming Perl, known to many Perl programmers as the . Explore research at Microsoft, a site featuring the impact of research along with publications, products, downloads, and research careers. Perl 4 went through a series of maintenance releases, culminating in Perl 4.036 in 1993. At that point, Wall abandoned Perl 4 to begin work on Perl 5. My question is simple, but the answer escapes me. To all you devoted Allen Bradley people and to everyone else who uses PLCs, why do you pay for their programming. Apple’s China Problem: WeChat Friday. Ben Thompson had a great column this week, in the wake of Apple’s quarterly results and Microsoft’s. So what has my personal experience been? As I said earlier, I knew little about how Valve worked when I started here, and my introduction to the company was not at. At the same time, the Perl version number was bumped to 4, not to mark a major change in the language but to identify the version that was well documented by the book. Early Perl 5. At that point, Wall abandoned Perl 4 to begin work on Perl 5. Local, state, and wire news and commentary. Photo galleries, business and obituaries. The GNU Compiler Collection (GCC) is a compiler system produced by the GNU Project supporting various programming languages. GCC is a key component of the GNU. But one doesn’t want to be uninformed! So here is my solution, sort of, when I can restrain myself from nervously tapping and clicking my phone for new news, kind. Originally published in the book Open Sources. Richard Stallman was never a supporter of “open source”, but contributed this. Initial design of Perl 5 continued into 1. The perl. 5- portersmailing list was established in May 1. Perl 5 to different platforms. It remains the primary forum for development, maintenance, and porting of Perl 5. Importantly, modules provided a mechanism for extending the language without modifying the interpreter. This allowed the core interpreter to stabilize, even as it enabled ordinary Perl programmers to add new language features. Perl 5 has been in active development since then. Perl 5. 0. 01 was released on March 1. Perl 5. 0. 02 was released on February 2. This allowed module authors to make subroutines that behaved like Perl builtins. Perl 5. 0. 03 was released June 2. One of the most important events in Perl 5 history took place outside of the language proper and was a consequence of its module support. On October 2. 6, 1. Comprehensive Perl Archive Network (CPAN) was established as a repository for Perl modules and Perl itself; as of May 2. Another significant development was the inclusion of the CGI. This release included several enhancements to the regex engine, new hooks into the backend through the B: :* modules, the qr// regex quote operator, a large selection of other new core modules, and added support for several more operating systems, including Be. OS. Major changes included 6. Unicode string representation, large file support (i. The process resulted in 3. RFC (request for comments) documents that were to be used in guiding development of Perl 6. They were presented as a digest of the RFCs, rather than a formal document. At this point, Perl 6 existed only as a description of a language. Perl 5. 8 was first released on July 1. Perl 5. 8 improved Unicode support, added a new I/O implementation, added a new thread implementation, improved numeric accuracy, and added several new modules. In February 2. 00. Audrey Tang began work on Pugs, a Perl 6 interpreter written in Haskell. This effort stalled in 2. Perl 5. 1. 0. 0 included notable new features, which brought it closer to Perl 6. These included a switch statement (called . As of November 2. Rakudo Perl has had regular monthly releases and now is the most complete implementation of Perl 6. A major change in the development process of Perl 5 occurred with Perl 5. By that plan, bugfix point releases will follow the stable releases every three months. On April 1. 2, 2. Perl 5. 1. 2. 0 was released. Notable core enhancements include new package NAME VERSION syntax, the Yada Yada operator (intended to mark placeholder code that is not yet implemented), implicit strictures, full Y2. DTrace support, and Unicode 5. The latest version of that branch, 5. November 1. 0, 2. On May 1. 4, 2. 01. Perl 5. 1. 4 was released. JSON support is built- in as of 5. The latest version of that branch, 5. March 1. 0, 2. 01. On May 2. 0, 2. 01. Perl 5. 1. 6 was released. Notable new features include the ability to specify a given version of Perl that one wishes to emulate, allowing users to upgrade their version of Perl, but still run old scripts that would normally be incompatible. Notable new features include the new dtrace hooks, lexical subs, more CORE: : subs, overhaul of the hash for security reasons, support for Unicode 6. Notable new features include subroutine signatures, hash slices/new slice syntax, postfix dereferencing (experimental), Unicode 6. The PONIE Project existed from 2. Perl 5 and Perl 6. It was an effort to rewrite the Perl 5 interpreter to run on Parrot, the Perl 6 virtual machine. The goal was to ensure the future of the millions of lines of Perl 5 code at thousands of companies around the world. Some of the improvements made to the Perl 5 interpreter as part of PONIE were folded into that project. Wall wanted to give the language a short name with positive connotations; he claims that he considered (and rejected) every three- and four- letter word in the dictionary. He also considered naming it after his wife Gloria. Wall discovered the existing PEARL programming language before Perl's official release and changed the spelling of the name. When referring to the interpreter program itself, the name is often uncapitalized (perl) because most Unix- like file systems are case- sensitive. Before the release of the first edition of Programming Perl, it was common to refer to the language as perl; Randal L. Schwartz, however, capitalized the language's name in the book to make it stand out better when typeset. This case distinction was subsequently documented as canonical. Licensing for commercial use is decided on a case by case basis. The second slogan is . Perl is procedural in nature, with variables, expressions, assignment statements, brace- delimited blocks, control structures, and subroutines. Perl also takes features from shell programming. All variables are marked with leading sigils, which allow variables to be interpolated directly into strings. However, unlike the shell, Perl uses sigils on all accesses to variables, and unlike most other programming languages that use sigils, the sigil doesn't denote the type of the variable but the type of the expression. So for example, to access a list of values in a hash, the sigil for an array (. Perl also has many built- in functions that provide tools often used in shell programming (although many of these tools are implemented by programs external to the shell) such as sorting, and calling operating system facilities. Perl takes lists from Lisp, hashes (. These simplify and facilitate many parsing, text- handling, and data- management tasks. Also shared with Lisp are the implicit return of the last value in a block, and the fact that all statements have a value, and thus are also expressions and can be used in larger expressions themselves. Perl 5 added features that support complex data structures, first- class functions (that is, closures as values), and an object- oriented programming model. These include references, packages, class- based method dispatch, and lexically scoped variables, along with compiler directives (for example, the strict pragma). A major additional feature introduced with Perl 5 was the ability to package code as reusable modules. Wall later stated that . The interpreter knows the type and storage requirements of every data object in the program; it allocates and frees storage for them as necessary using reference counting (so it cannot deallocate circular data structures without manual intervention). Legal type conversions — for example, conversions from number to string — are done automatically at run time; illegal type conversions are fatal errors. The design of Perl can be understood as a response to three broad trends in the computer industry: falling hardware costs, rising labor costs, and improvements in compiler technology. Many earlier computer languages, such as Fortran and C, aimed to make efficient use of expensive computer hardware. In contrast, Perl was designed so that computer programmers could write programs more quickly and easily. Perl has many features that ease the task of the programmer at the expense of greater CPU and memory requirements. These include automatic memory management; dynamic typing; strings, lists, and hashes; regular expressions; introspection; and an eval() function. Perl follows the theory of . Examples include Huffman coding (common constructions should be short), good end- weighting (the important information should come first), and a large collection of language primitives. Perl favors language constructs that are concise and natural for humans to write, even where they complicate the Perl interpreter. Perl's syntax reflects the idea that . Array indices and hash keys use different kinds of braces. Strings and regular expressions have different standard delimiters. This approach can be contrasted with a language such as Lisp, where the same basic syntax, composed of simple and universal symbolic expressions, is used for all purposes. Perl does not enforce any particular programming paradigm (procedural, object- oriented, functional, or others) or even require the programmer to choose among them. There is a broad practical bent to both the Perl language and the community and culture that surround it. The preface to Programming Perl begins: . It includes many features, tolerates exceptions to its rules, and employs heuristics to resolve syntactical ambiguities. Because of the forgiving nature of the compiler, bugs can sometimes be hard to find. Perl's function documentation remarks on the variant behavior of built- in functions in list and scalar contexts by saying, . There has been only one implementation of the interpreter, and the language has evolved along with it. That interpreter, together with its functional tests, stands as a de facto specification of the language. Perl 6, however, started with a specification.
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