| Title: | Match Regular Expressions with a Nicer 'API' |
|---|---|
| Description: | A small wrapper on 'regexpr' to extract the matches and captured groups from the match of a regular expression to a character vector. |
| Authors: | Gabor Csardi |
| Maintainer: | Gabor Csardi <[email protected]> |
| License: | MIT + file LICENSE |
| Version: | 2.0.0.9000 |
| Built: | 2024-06-26 03:45:14 UTC |
| Source: | https://github.com/gaborcsardi/rematch |
This function is a small wrapper on the regexpr
base R function, to provide an API that is easier to use.
re_match(pattern, text, ...)re_match(pattern, text, ...)
pattern |
Regular expression, defaults to be a PCRE
expression. See |
text |
Character vector. |
... |
Additional arguments to pass to
|
Currently only the first occurence of the pattern is used.
A character matrix of the matched (sub)strings.
The first column is always the full match. This column is
named .match. The result of the columns are capture groups,
with appropriate column names, if the groups are named.
dates <- c("2016-04-20", "1977-08-08", "not a date", "2016", "76-03-02", "2012-06-30", "2015-01-21 19:58") isodate <- "([0-9]{4})-([0-1][0-9])-([0-3][0-9])" re_match(text = dates, pattern = isodate) # The same with named groups isodaten <- "(?<year>[0-9]{4})-(?<month>[0-1][0-9])-(?<day>[0-3][0-9])" re_match(text = dates, pattern = isodaten)dates <- c("2016-04-20", "1977-08-08", "not a date", "2016", "76-03-02", "2012-06-30", "2015-01-21 19:58") isodate <- "([0-9]{4})-([0-1][0-9])-([0-3][0-9])" re_match(text = dates, pattern = isodate) # The same with named groups isodaten <- "(?<year>[0-9]{4})-(?<month>[0-1][0-9])-(?<day>[0-3][0-9])" re_match(text = dates, pattern = isodaten)
This function is a thin wrapper on the gregexpr
base R function, to provide an API that is easier to use. It is
similar to re_match, but extracts all matches, including
potentially named capture groups.
re_match_all(pattern, text, ...)re_match_all(pattern, text, ...)
pattern |
Regular expression, defaults to be a PCRE
expression. See |
text |
Character vector. |
... |
Additional arguments to pass to
|
A list of character matrices. Each list element contains the
matches of one string in the input character vector. Each matrix
has a .match column that contains the matching part of the
string. Additional columns are added for capture groups. For named
capture groups, the columns are named.
A small wrapper on 'regexpr' to extract the matches and captured
groups from the match of a regular expression to a character vector.
See re_match.