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| − | {{title|Regular expressions library}}
| + | SCREW you Ads ..... Ads are every where ...... |
| − | {{cpp/regex/navbar}}
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| − | The regular expressions library provides a class that represents [[enwiki:Regular expression|regular expressions]], which are a kind of mini-language used to perform pattern matching within strings. Almost all operations with regexes can be characterized by operating on several of the following objects:
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| − | * '''Target sequence'''. The character sequence that is searched for a pattern. This may be a range specified by two iterators, a null-terminated character string or a {{lc|std::string}}.
| + | BOTS are everywhere .... |
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| − | * '''Pattern'''. This is the regular expression itself. It determines what constitutes a match. It is an object of type {{lc|std::basic_regex}}, constructed from a string with special syntax. See {{lc|std::regex_constants::syntax_option_type|regex_constants::syntax_option_type}} for the description of supported syntax variations.
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| − | * '''Matched array'''. The information about matches may be retrieved as an object of type {{lc|std::match_results}}.
| + | Software job sucks ...... |
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| − | * '''Replacement string'''. This is a string that determines how to replace the matches, see {{lc|std::regex_constants::match_flag_type|regex_constants::match_flag_type}} for the description of supported syntax variations.
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| − | ===Main classes===
| + | But this is page editing stuff is so much fun ..... |
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| − | These classes encapsulate a regular expression and the results of matching a regular expression within a target sequence of characters.
| + | you see, its these little things that do put a smile on my face ..... |
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| − | {{dsc begin}}
| + | I dont ask for much ...... just some harmless fun ..... |
| − | {{dsc inc | cpp/regex/dsc basic_regex }}
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| − | {{dsc inc | cpp/regex/dsc sub_match }}
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| − | {{dsc inc | cpp/regex/dsc match_results }}
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| − | {{dsc end}}
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| − | ===Algorithms===
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| − | These functions are used to apply the regular expression encapsulated in a regex to a target sequence of characters.
| + | Hey Hey .... don't blame mee ..... I am just having some "harmless" fun .... |
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| − | {{dsc begin}}
| + | hehehehehehehehehehehehehehehhe |
| − | {{dsc inc | cpp/regex/dsc regex_match }}
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| − | {{dsc inc | cpp/regex/dsc regex_search }}
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| − | {{dsc inc | cpp/regex/dsc regex_replace }}
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| − | {{dsc end}}
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| − | ===Iterators===
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| − | The regex iterators are used to traverse the entire set of regular expression matches found within a sequence.
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| − | {{dsc begin}}
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| − | {{dsc inc | cpp/regex/dsc regex_iterator }}
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| − | {{dsc inc | cpp/regex/dsc regex_token_iterator }}
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| − | {{dsc end}}
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| − | ===Exceptions===
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| − | This class defines the type of objects thrown as exceptions to report errors from the regular expressions library.
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| − | {{dsc begin}}
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| − | {{dsc inc | cpp/regex/dsc regex_error }}
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| − | {{dsc end}}
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| − | ===Traits===
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| − | The regex traits class is used to encapsulate the localizable aspects of a regex.
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| − | {{dsc begin}}
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| − | {{dsc inc | cpp/regex/dsc regex_traits }}
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| − | {{dsc end}}
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| − | ===Constants===
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| − | {{dsc begin}}
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| − | {{dsc namespace | std::regex_constants }}
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| − | {{dsc inc | cpp/regex/dsc syntax_option_type}}
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| − | {{dsc inc | cpp/regex/dsc match_flag_type}}
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| − | {{dsc inc | cpp/regex/dsc error_type}}
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| − | {{dsc end}}
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| − | ===Example===
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| − | {{example
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| − | | code=
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| − | #include <iostream>
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| − | #include <iterator>
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| − | #include <string>
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| − | #include <regex>
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| − | int main()
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| − | {
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| − | std::string s = "Some people, when confronted with a problem, think "
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| − | "\"I know, I'll use regular expressions.\" "
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| − | "Now they have two problems.";
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| − | std::regex self_regex("REGULAR EXPRESSIONS",
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| − | std::regex_constants::ECMAScript {{!}} std::regex_constants::icase);
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| − | if (std::regex_search(s, self_regex)) {
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| − | std::cout << "Text contains the phrase 'regular expressions'\n";
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| − | }
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| − | std::regex word_regex("(\\w+)");
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| − | auto words_begin =
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| − | std::sregex_iterator(s.begin(), s.end(), word_regex);
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| − | auto words_end = std::sregex_iterator();
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| − | std::cout << "Found "
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| − | << std::distance(words_begin, words_end)
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| − | << " words\n";
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| − | const int N = 6;
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| − | std::cout << "Words longer than " << N << " characters:\n";
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| − | for (std::sregex_iterator i = words_begin; i != words_end; ++i) {
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| − | std::smatch match = *i;
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| − | std::string match_str = match.str();
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| − | if (match_str.size() > N) {
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| − | std::cout << " " << match_str << '\n';
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| − | }
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| − | }
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| − | std::regex long_word_regex("(\\w{7,})");
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| − | std::string new_s = std::regex_replace(s, long_word_regex, "[$&]");
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| − | std::cout << new_s << '\n';
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| − | }
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| − | | output=
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| − | Text contains the phrase 'regular expressions'
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| − | Found 20 words
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| − | Words longer than 6 characters:
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| − | confronted
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| − | problem
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| − | regular
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| − | expressions
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| − | problems
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| − | Some people, when [confronted] with a [problem], think
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| − | "I know, I'll use [regular] [expressions]." Now they have two [problems].
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| − | }}
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| − | {{langlinks|ar|de|es|fr|it|ja|ko|pt|ru|zh}}
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SCREW you Ads ..... Ads are every where ......
I dont ask for much ...... just some harmless fun .....
