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Matching Wildcards
In computer science, an algorithm for matching wildcards (also known as globbing) is useful in comparing text strings that may contain wildcard syntax. Common uses of these algorithms include command-line interfaces, e.g. the Bourne shell or Microsoft Windows command-line or text editor or file manager, as well as the interfaces for some search engines and databases. Wildcard matching is a subset of the problem of matching regular expressions and string matching in general. The problem A wildcard matcher tests a wildcard pattern ''p'' against an input string ''s''. It performs an ''anchored'' match, returns true only when ''p'' matches the entirety of ''s''. The pattern can be based on any common syntax (see globbing), but on Windows programmers tend to only discuss a simplified syntax supported by the native C runtime: * No escape characters are defined * Wildcards: matches exactly one occurrence of any character. matches arbitrary many (including zero) occurrences of any cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical disciplines (including the design and implementation of Computer architecture, hardware and Computer programming, software). Computer science is generally considered an area of research, academic research and distinct from computer programming. Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and for preventing Vulnerability (computing), security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Progr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wildmat
wildmat is a pattern matching library developed by Rich Salz. Based on the wildcard syntax already used in the Bourne shell, wildmat provides a uniform mechanism for matching patterns across applications with simpler syntax than that typically offered by regular expressions. Patterns are implicitly anchored at the beginning and end of each string when testing for a match. In June 2019, Rich Salz released the original version of the now-defunct library on GitHub under a public domain dedication. Pattern matching operations There are five pattern matching operations other than a strict one-to-one match between the pattern and the source to be checked for a match. * Asterisk ( *) to match any sequence of zero or more characters. * Question mark ( ?) to match any single character. * Set of specified characters. It is specified as a list of characters, or as a range of characters where the beginning and end of the range are separated by a minus (or dash) character, or as any combin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glob (programming)
In computer programming, glob () patterns specify sets of filenames with wildcard characters. For example, the Unix Bash shell command mv *.txt textfiles/ moves (mv) all files with names ending in .txt from the current directory to the directory textfiles. Here, * is a wildcard standing for "any string of characters except /" and *.txt is a glob pattern. The other common wildcard is the question mark (?), which stands for one character. For example, mv ?.txt shorttextfiles/ will move all files named with a single character followed by .txt from the current directory to directory shorttextfiles, while ??.txt would match all files whose name consists of 2 characters followed by .txt. In addition to matching filenames, globs are also used widely for matching arbitrary strings ( wildcard matching). In this capacity a common interface is fnmatch. Origin The glob command, short for ''global'', originates in the earliest versions of Bell Labs' Unix. The command interpreters of the ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pattern Calculus
Pattern calculus bases all computation on pattern matching of a very general kind. Like lambda calculus, it supports a uniform treatment of function evaluation. Also, it allows functions to be passed as arguments and returned as results. In addition, pattern calculus supports uniform access to the internal structure of arguments, be they pairs or lists or trees. Also, it allows patterns to be passed as arguments and returned as results. Uniform access is illustrated by a pattern-matching function that computes the size of an arbitrary data structure. In the notation of the programming language A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language. The description of a programming ... bondi, it is given by the recursive function let rec size = , x y -> (size x) + (size y) , x -> 1 The second, or ''default case'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pattern Matching
In computer science, pattern matching is the act of checking a given sequence of tokens for the presence of the constituents of some pattern. In contrast to pattern recognition, the match usually has to be exact: "either it will or will not be a match." The patterns generally have the form of either sequences or tree structures. Uses of pattern matching include outputting the locations (if any) of a pattern within a token sequence, to output some component of the matched pattern, and to substitute the matching pattern with some other token sequence (i.e., search and replace). Sequence patterns (e.g., a text string) are often described using regular expressions and matched using techniques such as backtracking. Tree patterns are used in some programming languages as a general tool to process data based on its structure, e.g. C#, F#, Haskell, ML, Python, Ruby, Rust, Scala, Swift and the symbolic mathematics language Mathematica have special syntax for expressing tree patt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thompson's Construction
In computer science, Thompson's construction algorithm, also called the McNaughton–Yamada–Thompson algorithm, is a method of transforming a regular expression into an equivalent nondeterministic finite automaton (NFA). This NFA can be used to match strings against the regular expression. This algorithm is credited to Ken Thompson. Regular expressions and nondeterministic finite automata are two representations of formal languages. For instance, text processing utilities use regular expressions to describe advanced search patterns, but NFAs are better suited for execution on a computer. Hence, this algorithm is of practical interest, since it can compile regular expressions into NFAs. From a theoretical point of view, this algorithm is a part of the proof that they both accept exactly the same languages, that is, the regular languages. An NFA can be made deterministic by the powerset construction and then be minimized to get an optimal automaton corresponding to the given r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glob (programming)
In computer programming, glob () patterns specify sets of filenames with wildcard characters. For example, the Unix Bash shell command mv *.txt textfiles/ moves (mv) all files with names ending in .txt from the current directory to the directory textfiles. Here, * is a wildcard standing for "any string of characters except /" and *.txt is a glob pattern. The other common wildcard is the question mark (?), which stands for one character. For example, mv ?.txt shorttextfiles/ will move all files named with a single character followed by .txt from the current directory to directory shorttextfiles, while ??.txt would match all files whose name consists of 2 characters followed by .txt. In addition to matching filenames, globs are also used widely for matching arbitrary strings ( wildcard matching). In this capacity a common interface is fnmatch. Origin The glob command, short for ''global'', originates in the earliest versions of Bell Labs' Unix. The command interpreters of the ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regular Expression
A regular expression (shortened as regex or regexp; sometimes referred to as rational expression) is a sequence of characters that specifies a search pattern in text. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings, or for input validation. Regular expression techniques are developed in theoretical computer science and formal language theory. The concept of regular expressions began in the 1950s, when the American mathematician Stephen Cole Kleene formalized the concept of a regular language. They came into common use with Unix text-processing utilities. Different syntaxes for writing regular expressions have existed since the 1980s, one being the POSIX standard and another, widely used, being the Perl syntax. Regular expressions are used in search engines, in search and replace dialogs of word processors and text editors, in text processing utilities such as sed and AWK, and in lexical analysis. Most gener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Code Project
Code Project (formerly The Code Project) is a community for computer programmers with articles on different topics and programming languages such as web development, software development, C++, Java, and other topics. Once a visitor registers a user account on the site, they can gain reputation which allows users to unlock different privileges such as the ability to store personal files in the user's account area, have live hyperlinks in their profile biography, and more. Members can also write and upload their own articles and code for other visitors to view. Articles can be related to general programming, Graphical User Interface, GUI design, algorithms or collaboration. Most of the articles are uploaded by visitors and do not come from an external source. Nearly every article is accompanied with source code and examples which can be downloaded independently. Most articles and sources are released under the Code Project Open License (CPOL), although the license can be configure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krauss Wildcard-matching Algorithm
In computer science, the Krauss wildcard-matching algorithm is a pattern matching algorithm. Based on the wildcard syntax in common use, e.g. in the Microsoft Windows command-line interface, the algorithm provides a non-recursive mechanism for matching patterns in software applications, based on syntax simpler than that typically offered by regular expressions. History The algorithm is based on a history of development, correctness and performance testing, and programmer feedback that began with an unsuccessful search for a reliable non-recursive algorithm for matching wildcards. An initial algorithm, implemented in a single while loop, quickly prompted comments from software developers, leading to improvements. Ongoing comments and suggestions culminated in a revised algorithm still implemented in a single while loop but refined based on a collection of test cases and a performance profiler. The experience tuning the single while loop using the profiler prompted development of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glibc
The GNU C Library, commonly known as glibc, is the GNU Project's implementation of the C standard library. Despite its name, it now also directly supports C++ (and, indirectly, other programming languages). It was started in the 1980s by the Free Software Foundation (FSF) for the GNU operating system. Released under the GNU Lesser General Public License, glibc is free software. The GNU C Library project provides the core libraries for the GNU system, as well as many systems that use Linux as the kernel. These libraries provide critical APIs including ISO C11, POSIX.1-2008, BSD, OS-specific APIs and more. These APIs include such foundational facilities as open, read, write, malloc, printf, getaddrinfo, dlopen, pthread_create, crypt, login, exit and more. History The glibc project was initially written mostly by Roland McGrath, working for the Free Software Foundation (FSF) in the 1980s as a teenager. In February 1988, FSF described glibc as having nearly completed the func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guido Van Rossum
Guido van Rossum (; born 31 January 1956) is a Dutch programmer best known as the creator of the Python programming language, for which he was the " benevolent dictator for life" (BDFL) until he stepped down from the position on 12 July 2018. He remained a member of the Python Steering Council through 2019, and withdrew from nominations for the 2020 election. Life and education Van Rossum was born and raised in the Netherlands, where he received a master's degree in mathematics and computer science from the University of Amsterdam in 1982. He received a bronze medal in 1974 in the International Mathematical Olympiad. He has a brother, Just van Rossum, who is a type designer and programmer who designed the typeface used in the "Python Powered" logo. Van Rossum lives in Belmont, California, with his wife, Kim Knapp, and their son. According to his home page and Dutch naming conventions, the " ''van''" in his name is capitalized when he is referred to by surname alone, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
