R/in-notin.R

In mtfairbanks/gdt: Tidy Interface to 'data.table'

#' Fast `%in%` and `%notin%` operators
#'
#' @description
#' Check whether values in a vector are in or not in another vector.
#'
#' Built using `data.table::'%chin%'` and `vctrs::vec_in()` for performance.
#'
#' @param x A vector of values to check if they exist in y
#' @param y A vector of values to check if x values exist in
#'
#' @details
#' Falls back to `base::'%in%'` when x and y don't share a common type.
#' This means that the behaviour of `base::'%in%'` is preserved (e.g. `"1" %in% c(1, 2)` is `TRUE`)
#' but loses the speedup provided by `vctrs::vec_in()`.
#'
#' @export
#'
#' @examples
#' df <- tidytable(x = 1:4, y = 1:4)
#'
#' df %>%
#'   filter(x %in% c(2, 4))
#'
#' df %>%
#'   filter(x %notin% c(2, 4))
#' @rdname in-notin
'%in%' <- function(x, y) {
  if (is.character(x) && is.character(y)) {
    x %chin% y
  } else if (vec_ptype_compatible(x, y)) {
    vec_in(x, y)
  } else {
    # #565/#632
    base::'%in%'(x, y)
  }
}

#' @export
#' @rdname in-notin
'%notin%' <- function(x, y) {
  !(x %in% y)
}