/yare

yet another regular expression

Primary LanguageC++MIT LicenseMIT

yare

Yet another regular expression, single-header-file, supports UTF-8 and ASCII only.

There is a common regular expression, commonregex, supports universal code

Syntax

Metacharacter Description
. Matches any single character (many applications exclude newlines('\n'). Within bracket expressions, the dot character matches a literal dot. For example, a.c matches "abc", etc., but [a.c] matches only "a", ".", or "c".
[...] A bracket expression. Matches a single character that is contained within the brackets. For example, [abc] matches "a", "b", or "c". [a-z] specifies a range which matches any lowercase letter from "a" to "z". These forms can be mixed: [abcx-z] matches "a", "b", "c", "x", "y", or "z", as does [a-cx-z].
[^...] Matches a single character that is not contained within the brackets. For example, [^abc] matches any character other than "a", "b", or "c". [^a-z] matches any single character that is not a lowercase letter from "a" to "z". Likewise, literal characters and ranges can be mixed.
^ Matches the starting position within the string.
$ Matches the ending position of the string or the position just before a string-ending newline.
* Matches the preceding element zero or more times. For example, ab*c matches "ac", "abc", "abbbc", etc. [xyz]* matches "", "x", "y", "z", "zx", "zyx", "xyzzy", and so on. (ab)* matches "", "ab", "abab", "ababab", and so on.
+ Matches the preceding element one or more times. For example, ab+c matches "abc", "abbc", "abbbc", and so on, but not "ac".
? Matches the preceding element zero or one time. For example, ab?c matches only "ac" or "abc".
| The choice (also known as alternation or set union) operator matches either the expression before or the expression after the operator. For example, `abc
() Defines a marked subexpression. The string matched within the parentheses can be recalled later.
{n} Matches the preceding element n times.
{n,} Matches the preceding element at least n times.
{n, m} Matches the preceding element at least m and not more than n times. For example, a{3,5} matches only "aaa", "aaaa", and "aaaaa". This is not found in a few older instances of regexes.
(?<name>) Matches what the name marked subexpression matched.
(?<name>...) Defines a marked subexpression. The string matched within the parentheses can be recalled later by the name.
\s Matches a whitespace character; same as [ \f\n\r\t\v].
\S Matches anything BUT a whitespace; same as [^ \f\n\r\t\v].
\l Matches a lowercase letter; same as [a-z].
\L Matches anything BUT a lowercase letter; same as [^a-z].
\u Matched a uppercase letter; same as [A-Z].
\U Matched anything BUT a uppercase letter; same as [^A-Z].
\w Matches an alphanumeric character, including "_"; same as [A-Za-z0-9_].
\W Matches a non-alphanumeric character, excluding "_"; same as [^A-Za-z0-9_].
\d Matches a digit; same as [0-9].
\D Matches a non-digit; same as [^0-9].
\cX Matches a control character indicated by X. For example, \cM matches a Control-M or carriage return. The value of x must be one of A-Z or a-z. Otherwise, treat c as a literal 'c' character.
\0, \a, \b, \t, \n, \v, \f, \r, \r Matches a escape character.
Examples
  • (?:<sec>25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9][0-9]|[0-9])(\\.(?:<sec>)){3} denotes ipv4 address, such as 192.168.1.1, 255.255.255.0 and so on.

Interface

Class
Class Name Description
Pattern Pattern object, provides methods for matching, searching and replacing.
Functions
Function Name Description
match attempts to match a regular expression to an entire character sequence.
search attempts to match a regular expression to any part of a character sequence.
replace replaces occurrences of a regular expression with formatted replacement text.
matches attempts to match a regular expression to some entire character sequences.
Examples
// e.g. Pattern's methods
#include "yare.hpp"

auto pattern = yare::Pattern("(?:<sec>25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9][0-9]|[0-9])(\\.(?:<sec>)){3}")
auto match_result = pattern.match("192.168.1.1");
auto search_result = pattern.search("ipv4 address: 123.123.123.123");
auto replace_result = pattern.replace("ipv4 address: 123.123.123.123", "***.***.***.***");
auto matches_result = pattern.matches("<meta test1> <meta test2>");
// e.g. normal functions
#include "yare.hpp"

auto match_result = yare::match("(?:<sec>25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9][0-9]|[0-9])(\\.(?:<sec>)){3}", "192.168.1.1");
auto search_result = yare::search("(?:<sec>25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9][0-9]|[0-9])(\\.(?:<sec>)){3}", "ipv4 address: 123.123.123.123");
auto replace_result = yare::replace("(?:<sec>25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9][0-9]|[0-9])(\\.(?:<sec>)){3}", "ipv4 address: 123.123.123.123", "***.***.***.***");
auto matches_result = yare::matches("<meta[^>]*>", "<meta test1> <meta test2>");