Replace parts of a string with new text.

str_replace_first(), str_replace_nth() and str_replace_last(): Replace the specified pattern occurrence in each string.

str_replace_all() Replace every pattern occurrence in each string.

Usage

str_replace_first(strings, pattern, replacement, fixed = FALSE)

str_replace_all(strings, pattern, replacement, fixed = FALSE)

str_replace_nth(strings, pattern, replacement, n, fixed = FALSE)

str_replace_last(strings, pattern, replacement, fixed = FALSE)

Arguments

strings

A character vector, where each element of the vector is a character string.

pattern

A single character string to be searched for in each element of strings. By default, pattern is interpreted as a regular expression (regex). If the fixed argument is set to TRUE, pattern will be treated as a literal string to be matched exactly.

replacement

A single string containing the text to replace the pattern with.

fixed

Logical; whether pattern should be matched exactly, treating regex special characters as regular string characters. Default FALSE.

n

(str_replace_nth only) Integer, the nth occurrence of the pattern to replace. Negative values count back from the end.

Value

str_replace_first(), str_replace_nth() and str_replace_last(): Returns an altered character vector of equal length to strings, with the first, nth and last pattern occurrence, respectively, replaced by the replacement text.

str_replace_all() Returns an altered character vector of equal length to strings, with every match in each string replaced.

Details

These functions are built using the base R regular expression functions. {suitestrings} uses Perl-compatible Regular Expressions (PCRE). This is achieved by setting perl = TRUE in the underlying base functions. See R's regexp documentation for info on the regex implementation. For complete syntax details see https://www.pcre.org/current/doc/html/

See also

sub() and gsub() for the base replacement functions that _first and _all wrap around, respectively.

regmatches<- for the base in-place replacement function that _nth and _last wrap around.

Examples

strings <- c("banana", "banana banana", "no match here")

str_replace_first(strings, "na", "NA")
#> [1] "baNAna"        "baNAna banana" "no match here"
str_replace_nth(strings, "na", "NA", 2)
#> [1] "banaNA"        "banaNA banana" "no match here"
str_replace_last(strings, "na", "NA")
#> [1] "banaNA"        "banana banaNA" "no match here"
str_replace_all(strings, "na", "NA")
#> [1] "baNANA"        "baNANA baNANA" "no match here"