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| | Regular expression - Wikipedia, the free encyclopedia |
 | | The origins of regular expressions lies in automata theory and formal language theory, both of which are part of theoretical computer science. | | | The integration of regular expressions in most computer languages is still very poor and, even though Perl's regular expression integration is one of the best around, part of the effort in the design of the future Perl6 is improving this integration. | | | Regular expressions correspond to the type 3 grammars of the Chomsky hierarchy and may be used to describe a regular language. |
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http://en.wikipedia.org/wiki/Regular_expression
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| | The Limbo Programming Language |
| | Expressions in Limbo are not reordered by the compiler; values are computed in accordance with the parse of the expression. | | | An identifier used in an expression is often a previously declared data object with a particular data type; when used as a term in an expression it denotes the value stored in the object, and the term has the declared object's type. | | | If a single expression is present in the list, the type and value are those of the expression; the parentheses affect only the binding of operators in the expression of which the term is a part. |
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http://www.vitanuova.com/inferno/papers/limbo.html
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| | Regular expression - Wikipedia, the free encyclopedia |
| | The integration of regular expressions in most computer languages is still very poor and, even though Perl's regular expression integration is one of the best around, part of the effort in the design of the future Perl6 is improving this integration. | | | It is possible to write an algorithm which for two given regular expressions decides whether the described languages are equal - essentially, it reduces each expression to a minimal deterministic finite state automaton and determines whether they are isomorphic (equivalent). | | | A regular expression (abbreviated as regexp, regex, or regxp, with plural forms regexps, regexes, or regexen) is a string that describes or matches a set of strings, according to certain syntax rules. |
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http://en.wikipedia.org/wiki/Regular_expression
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| | Programming Concepts - Prof. Holowczak |
| | In this section, we demonstrate how such expressions are written and evaluated in computer programming languages. | | | Understanding how to pose and evaluate Boolean logic expressions is a crucial skill for any programmer or indeed anyone who programs computers in a formal language (such as "C", Pascal, Fortran, SQL, etc.) or in a macro language such as shell scripts or MS Excel formulas and macros. | | | Boolean logic is called a Two Valued Logic because an expression may only take on one of two values: True or False. |
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http://cisnet.baruch.cuny.edu/holowczak/classes/programming
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| | Lisp programming language - Wikipedia, the free encyclopedia |
| | Program code is written using the same syntax as lists – the parenthesized S-expression syntax. | | | are a list of arguments, and the expression or expressions that the function evaluates to (the return value is the value of the last expression to be evaluated). | | | Expressions using these operators have the same surface appearance as function calls, but differ in that the arguments are not necessarily evaluated -- or, in the case of an iteration expression, may be evaluated more than once. |
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http://en.wikipedia.org/wiki/Lisp_programming_language
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| | Functional Programming |
| | Expressions are atoms which are variables or constants, lists of arbitrary length (which are also function applications), lambda-abstractions of one or more parameters, and other built-in functions. | | | As with mathematical expressions, it is characterized by the principle that the value of an expression depends only on the values of its subexpressions. | | | The definitions of the let and letrec expressions are restated in Figure N.6. |
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http://www.cs.jhu.edu/~jason/465/lambdacalc.html
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| | The Q Programming Language: |
| | As in other functional programming languages, all computations performed by Q scripts are expression evaluations: The user specifies an expression to be evaluated, the interpreter computes the value of that expression and prints it as the result of the computation. | | | However, in most programming languages expressions are merely treated as descriptions of computations to be performed in order to obtain the value of an expression, which usually belongs to some basic type provided by the language. | | | As mentioned in the previous section, in the Q language function definitions take the form of equations which specify how a given expression pattern, the left-hand side of the equation, is transformed into a new expression, the right-hand side of the equation. |
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http://q-lang.sourceforge.net/qdoc.html
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| | The Unlambda Programming Language |
| | It is not fundamentally difficult, being mainly a question of applying abstraction elimination to expressions of the untyped lambda calculus (of course, obtaining these expressions in the first place is not necessarily evident); if you're messy it will turn into a nightmare. | | | If several lambdas need to be eliminated from one expression, the trick is to start with the innermost ones, and to eliminate the outermost lambdas last. | | | fixed point theorems in logic, such a program exists in any Turing-complete language in which printing an arbitrary string is possible (by a computable program of the string — a technical criterion which is satisfied in all programming languages in existence). |
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http://www.eleves.ens.fr:8080/home/madore/programs/unlambda
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| | Expressions, Statements, and Blocks |
| | The job of an expression is twofold: to perform the computation indicated by the elements of the expression and to return a value that is the result of the computation. | | | Among other things, expressions are used to compute and to assign values to variables and to help control the execution flow of a program. | | | An expression is a series of variables, operators, and method calls (constructed according to the syntax of the language) that evaluates to a single value. |
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http://java.sun.com/docs/books/tutorial/java/nutsandbolts/expressions.html
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| | PlanetMath: regular expression |
| | Here is an example of a regular expression that specifies a grammar that generates the binary representation of all multiples of 3 (and only multiples of 3). | | | One can understand the language described by a regular expression in another way, by viewing the regular expression operators as shorthand for various set-theoretic operations. | | | This is version 5 of regular expression, born on 2002-02-24, modified 2004-04-03. |
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http://planetmath.org/encyclopedia/RegularExpression.html
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| | Lisp programming language - Wikipedia, the free encyclopedia |
| | are a list of arguments, and the expression or expressions that the function evaluates to (the return value is the value of the last expression to be evaluated). | | | McCarthy published its design in a paper in Communications of the ACM in 1960, entitled "Recursive Functions of Symbolic Expressions and Their Computation by Machine, Part I". | | | When an expression is evaluated, it produces a value (or list of values), which then can be embedded into other expressions. |
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http://en.wikipedia.org/wiki/Lisp_programming_language
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| | 4.2.1 Regular Expression Syntax |
| | Matches whatever regular expression is inside the parentheses, but the substring matched by the group cannot be retrieved after performing a match or referenced later in the pattern. | | | A regular expression (or RE) specifies a set of strings that matches it; the functions in this module let you check if a particular string matches a given regular expression (or if a given regular expression matches a particular string, which comes down to the same thing). | | | Matches whatever regular expression is inside the parentheses, and indicates the start and end of a group; the contents of a group can be retrieved after a match has been performed, and can be matched later in the string with the |
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http://www.python.org/doc/current/lib/re-syntax.html
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| | Regular Expressions |
| | Regular expressions are a powerful way of specifying complex search and replace operations. | | | An ordinary character is a simple regular expression which matches that character and nothing else. | | | Nontrivial regular expressions use certain special constructs so that they can match more than one string. |
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http://www.emerson.emory.edu/services/editors/ne/Regular_Expressions.html
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| | Regular Expression HOWTO |
| | Regular expressions are often used to dissect strings by writing a RE divided into several subgroups which match different components of interest. | | | This can be handled by writing a regular expression which matches an entire header line, and has one group which matches the header name, and another group which matches the header's value. | | | Since regular expressions are used to operate on strings, we'll begin with the most common task: matching characters. |
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http://www.amk.ca/python/howto/regex
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| | Freeware Download: Programming |
| | The Regular Expression Component Library is an easy to use library for searching and/or replacing strings or data in files using regular expressions in non-managed C++ code. | | | The Regular Expression Component Library is an easy to use library for searching and/or replacing strings or data in files using regular expressions. | | | The interface is simple enough for a complete novice to get started in data programming yet the query language and function library provide all the power required by professional developers. |
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http://www.dirfile.com/freeware/programming.htm
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| | Regular Expressions and the Java Programming Language |
| | Regular expression usage using this new package is Perl-like, so if you are familiar with using regular expressions in Perl, you can use the same expression syntax in the Java programming language. | | | The simplest form of a regular expression is a literal string, such as "Java" or "programming." Regular expression matching also allows you to test whether a string fits into a specific syntactic form, such as an email address. | | | Regular expressions can be put to use in applications to ensure data is formatted correctly before being entered into a database, or sent to some other part of an application, and they can be used for a wide variety of administrative tasks. |
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http://java.sun.com/developer/technicalArticles/releases/1.4regex
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| | Programming With Assertions |
| | By verifying that the boolean expression is indeed true, the assertion confirms your assumptions about the behavior of your program, increasing your confidence that the program is free of errors. | | | Because assertions may be disabled, programs must not assume that the boolean expression contained in an assertion will be evaluated. | | | The program would work fine when asserts were enabled, but would fail when they were disabled, as it would no longer remove the null elements from the list. |
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http://java.sun.com/j2se/1.4.2/docs/guide/lang/assert.html
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| | 4.2 re -- Regular expression operations |
| | Regular expression pattern strings may not contain null bytes, but can specify the null byte using the | | | This module provides regular expression matching operations similar to those found in Perl. | | | The second edition of the book no longer covers Python at all, but the first edition covered writing good regular expression patterns in great detail. |
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http://www.python.org/doc/current/lib/module-re.html
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| | Learning to Use Regular Expressions |
| | A space in a regular expression, by the way, matches a literal space in the target (this is unlike most programming languages or command-line tools, where spaces separate keywords). | | | The programming language Perl is probably the most sophisticated tool for regular expression processing, which explains much of its popularity. | | | Often if you find that your regular expressions are matching too much, a useful procedure is to reformulate the problem in your mind. |
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http://gnosis.cx/publish/programming/regular_expressions.html
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| | More AI...(GEP) Gene Expression Programming in C# and .NET |
| | Gene Expression programming (GEP) is also a subset of Genetic Algorithms, except it uses genomes whose strings of numbers represent symbols. | | | This can be accomplished simply by taking the difference between the resulting value of plugging the sides of the measured triangle into the genetic expression minus the measured hypotenuse, then taking the difference between a constant number (such as 100) and the value computed from the error. | | | The fitness function should give us the highest number for results that occur when walking the genetic expression that are closest to the measured value of our hypotenuse. |
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http://www.c-sharpcorner.com/Code/2002/Nov/GEPAlgorithm.asp
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| | The Regular Expression Rundown |
| | The expression can be a simple string, and the input data can be a named list of files. | | | Regular expressions evaluate text data and return an answer of true or false. | | | What data the expression evaluates and what transpires after a successful match depends entirely on the application. |
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http://www.webmonkey.com/geektalk/97/33/index3a.html
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| | Jakarta-Regexp 1.4 API: Class RE |
| | Regular expressions are pattern descriptions which enable sophisticated matching of strings. | | | Given a regular expression of "a*b" and an array of String objects of [foo, aab, zzz, aaaab], the array of Strings returned by grep would be [aab, aaaab]. | | | Match the current regular expression program against the current input string, starting at index i of the input string. |
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http://jakarta.apache.org/regexp/apidocs/org/apache/regexp/RE.html
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| | regex_proposal |
| | Regular expressions are used by many familiar Unix utilities, including egrep, grep, lex, and sed[1], and are supported directly in many programming languages including awk[1], perl[2], C#[3], and ECMAScript[4] (also known as JavaScript), and indeed are often used ubiquitously wherever text processing occurs. | | | Regular expression algorithms: iterator based non-member functions for searching for a match, and for finding an exact match (discussion). | | | Specifies that when a regular expression match is to be replaced by a new string, that the new string is constructed using the rules used by the Unix sed utility in IEEE Std 1003.1-2001, Portable Operating SystemInterface (POSIX), Shells and Utilities.. |
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http://anubis.dkuug.dk/jtc1/sc22/wg21/docs/papers/2003/n1429.htm
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| | Regular Expression Basics evolt.org |
| | Although regular expressions had their origins in neurophysiology in the 1940s and were developed by theoretical mathematicians in the 1950s and 1960s, the evolution and subsequent divergence of regex implementations was due to the independent development of various Unix tools such as grep, awk, sed, Emacs, and others. | | | It's not possible in general to match strings using regular expressions which are recursively defined. | | | takes a regular expression, a function, and a string, and repeatedly matches the regular expression against the string, each time replacing the matching bit how the function given tells it to. |
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http://www.evolt.org/article/rating/20/22700
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| | Regular Expressions |
| | The regular expression "^A" will match all lines that start with a capital A. The expression "A$" will match all lines that end with the capital A. If the anchor characters are not used at the proper end of the pattern, then they no longer act as anchors. | | | That is, the regular expression "0*" matches zero or more zeros, while the expression "[0-9]*" matches zero or more numbers. | | | Regular expressions confuse people because they look a lot like the file matching patterns the shell uses. |
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http://www.grymoire.com/Unix/Regular.html
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| | Chinese Language Keyboard |
| | However, because the Bicameral Keyboard can be directly utilized for scientific and technological communications, as well as business correspondence, the pictographic languages could maintain their predominant position in those societies that chose to retain pictographic expression. | | | What is required for efficient pictographic expression in terms of input speed is a character input device that can take full advantage of the small number of keystrokes required in pictographic expression as shown in Figure 1 while providing the means to rapidly do so with fewer keys that required by the Western Keyboard. | | | It is evident from this description that the Bicameral Keyboard is not simply an input device for communication, computing and typesetting but rather would become an integral part of the language itself. |
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http://www.pages.drexel.edu/~garfinkm/Picto.html
(2747 words)
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| | GameDev.net - Test Driving Expression Template Programming |
| | Lazy evaluation: As opposed to eager computation of expression, lazy evaluation delays the evaluation until the very moment it is needed. | | | And in order to introduce an interesting project to test drive with, you will be exposed to expression objects in the latter part of the article, where each action of an object does not result in a copy of itself, but merely an object representing that expression. | | | The down-side is, of course, at the point of evaluation cpu cycles is spent to evaluate the expression. |
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http://www.gamedev.net/reference/articles/article2114.asp
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| | ARS Based Programming: Fundamental And Without Limits |
| | This approach to programming is covered in detail in the book `Programmierung pur' (`Undiluted Programming') which has been published in April 2003 by the S.Toeche-Mittler Verlag in Darmstadt, Germany. | | | Whereas the Lambda Calculus gives functional programming its theoretical foundation, ARS is capable to provide a theoretical base for all three major programming paradigms, i.e. | | | EBNF notation define A++ as a programming language in contrast to the Lambda Calculus. |
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http://www.lambda-bound.com
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| | Etext Center: Services |
| | Regular expressions don't constitute a "language" in the way that C or Perl are languages or a tool in the way that sed or grep are tools; instead, regular expressions constitute a syntax which many languages and tools (including these) support. | | | If you're a programmer who's new to regular expressions, you can probably imagine the advantage of using Perl as a regex "wrapper." As a full-blown programming language, Perl allows you to embed regular expressions in file tests, control loops, output formats, and everything else. | | | Regular expressions ("regex's" for short) are sets of symbols and syntactic elements used to match patterns of text. |
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http://etext.lib.virginia.edu/services/helpsheets/unix/regex.html
(3310 words)
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| | Bourne Shell Programming |
| | Evaluates a boolean expression and exits with an exit code of zero if it is true, or non-zero if it is false. | | | expression is a string; this is generally either a variable or a backquoted command. | | | However, variables and backquoted expressions are expanded and replaced with their value. |
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http://www.ooblick.com/text/sh
(3310 words)
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