Replace Non-Alphanumeric Characters

Replace or remove non-alphanumeric characters, keeping dots and handling underscores as indicated by keep_underscores.

Usage

replace_nonalnum(x, replacement = "_", keep_underscore = TRUE)

Arguments

x

character vector with strings to remove non-alphanumeric characters from. Empty strings ("") are allowed.

replacement

character string used to replace non-alphanumeric characters. It might be empty (i.e., "") to remove instead of replace non-alphanumeric characters.

keep_underscore

TRUE or FALSE: keep underscores? If FALSE, underscores are replaced by replacement, which is only apparent if a non-default replacement is used such that it is not an underscore, see the last 'Example'.

Value

x with non-alphanumeric characters other than dots, as well as underscores if keep_underscores is FALSE, replaced by replacement. An empty string ("") is returned if the empty character string ("") is used for replacement and x does not contain non-replaced characters.

Details

This implementation uses the character class [:alnum:] that depends on the current locale, see the 'Programming Notes' in checkinput::all_names().

See also

trimws() to remove leading whitespace, trailing whitespace, or both; replace_vals(), with more relevant links, to replace specific values; checkinput::all_names() and checkinput::is_path() for checks on the validity of strings.

Other functions to check equality: are_equal(), check_case(), get_file_path(), not_in(), replace_vals(), signif_custom()

Other functions to modify character vectors: as.numeric_safe(), reexports, replace_vals(), signal_text(), unpaste_unquote(), vect_to_char(), wrap_text()

Examples

replace_nonalnum("a+b.txt")
#> [1] "a_b.txt"
replace_nonalnum("a b.txt")
#> [1] "a_b.txt"
replace_nonalnum("ab12._")  # returned unchanged
#> [1] "ab12._"
replace_nonalnum(c("a+b.txt", "a b.txt", "ab12._"))
#> [1] "a_b.txt" "a_b.txt" "ab12._" 

# Removing instead of replacing nonalphanumeric characters
replace_nonalnum("a+b.txt", replacement = "") # "ab.txt"
#> [1] "ab.txt"

# Handling underscores
replace_nonalnum("a+bc_d.txt", replacement = "",
                 keep_underscore = TRUE)  # "abc_d.txt"
#> [1] "abc_d.txt"
replace_nonalnum("a+bc_d.txt", replacement = "",
                 keep_underscore = FALSE) # "abcd.txt"
#> [1] "abcd.txt"
# Seems to keep the underscore because the
# default 'replacement' is an underscore
replace_nonalnum("a+bc_d.txt",
                 keep_underscore = FALSE) # "a_bc_d.txt"
#> [1] "a_bc_d.txt"