% Generated by tinyroxygen: do not edit by hand
% Please edit documentation in cache.R
\name{key_missing}
\alias{key_missing}
\alias{is.key_missing}
\title{Key Missing Sentinel}
\usage{
key_missing()
is.key_missing(x)
}

\arguments{
\item{x}{An object to test.}
}

\value{
\code{key_missing()} returns an object of class
  \code{"key_missing"}. \code{is.key_missing()} returns \code{TRUE} or
  \code{FALSE}.
}

\description{
\code{key_missing()} returns a sentinel object indicating
  that a requested key was not found in a cache. \code{is.key_missing()}
  tests whether a value is this sentinel. Mirrors
  \code{cachem::key_missing()} / \code{fastmap::key_missing()}.
}

