% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/hash.R
\name{hash}
\alias{hash}
\alias{hash_file}
\title{Hashing}
\usage{
hash(x)

hash_file(path)
}
\arguments{
\item{x}{An object.}

\item{path}{A character vector of paths to the files to be hashed.}
}
\value{
\itemize{
\item For \code{hash()}, a single character string containing the hash.
\item For \code{hash_file()}, a character vector containing one hash per file.
}
}
\description{
\itemize{
\item \code{hash()} hashes an arbitrary R object.
\item \code{hash_file()} hashes the data contained in a file.
}

The generated hash is guaranteed to be reproducible across platforms that
have the same endianness and are using the same R version.
}
\details{
These hashers use the XXH128 hash algorithm of the xxHash library, which
generates a 128-bit hash. Both are implemented as streaming hashes, which
generate the hash with minimal extra memory usage.

For \code{hash()}, objects are converted to binary using R's native serialization
tools. On R >= 3.5.0, serialization version 3 is used, otherwise version 2 is
used. See \code{\link[=serialize]{serialize()}} for more information about the serialization version.
}
\examples{
hash(c(1, 2, 3))
hash(mtcars)

authors <- file.path(R.home("doc"), "AUTHORS")
copying <- file.path(R.home("doc"), "COPYING")
hashes <- hash_file(c(authors, copying))
hashes

# If you need a single hash for multiple files,
# hash the result of `hash_file()`
hash(hashes)
}