R/split.R

In re2r: RE2 Regular Expression

## This file is part of the 're2r' package for R.
## Copyright (C) 2016, Qin Wenfeng
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#' Split a string into pieces.
#'
#' Split a string into pieces. Vectorised over string and pattern.
#'
#' @inheritParams re2_locate
#' @param n number of pieces to return. Default (Inf) for
#' \code{\link{re2_split}} uses all possible split positions.
#' For \code{\link{re2_split_fixed}}, if n is greater than
#'  the number of pieces, the result will be padded with
#'  empty strings.
#' @examples
#' re2_split("yabba dabba doo", " ")
#' re2_split_fixed(c("yabba dabba doo", "a bc"), " ", 2)
#' @return For \code{\link{re2_split_fixed}}, a character matrix with n columns.
#'
#' For \code{\link{re2_split}}, a list of character vectors.
#' @export
re2_split = function(string, pattern, n = Inf, parallel = FALSE, grain_size = 10000, ...) {
    if (is.character(pattern) || mode(pattern) == "logical") {
        pattern = re2(pattern, ...)
    }
    cpp_split(stri_enc_toutf8(string), pattern, n, FALSE,parallel,grain_size)
}

#' @rdname re2_split
#' @export
re2_split_fixed = function(string, pattern, n, parallel = FALSE, grain_size = 10000,  ...) {
    if (is.character(pattern) || mode(pattern) == "logical") {
        pattern = re2(pattern, ...)
    }
    cpp_split(stri_enc_toutf8(string), pattern, n, TRUE, parallel,grain_size)
}