Build a letter pattern

Matches alphabetical characters.

xp_build_letters(pattern = NULL, case = c("both", "lower", "upper"))

Arguments

pattern

(Optional) An existing pattern from a pipe.

case

Character. One of "both" (default), "lower", or "upper".

Value

A regexpert object.

Examples

# Match lowercase letters
xp_build_letters(case = "lower")
#> <regexpert pattern>
#>   [a-z]

# Build a username pattern (Letters followed by numbers)
xp_build_letters() %>% xp_op_repeat(1, Inf) %>% xp_build_digits()
#> <regexpert pattern>
#>   (?:[A-Za-z])+\d