% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/snapshot.R
\name{cer_snapshot}
\alias{cer_snapshot}
\title{Pin or inspect the session snapshot date}
\usage{
cer_snapshot(date)
}
\arguments{
\item{date}{ISO \code{"YYYY-MM-DD"} character, \code{Date}, or \code{POSIXct}.
Pass \code{NULL} to clear.}
}
\value{
Invisibly, the new pinned date (as \code{Date}), or \code{NULL}.
}
\description{
Call once at the top of an analysis script to declare the vintage
of CER data you intend to use. Every subsequent \verb{cer_*} fetch
records this date in the \code{cer_tbl} provenance header, in
\code{\link[=cer_manifest]{cer_manifest()}} entries, and in \code{\link[=cer_cite]{cer_cite()}} output.
}
\details{
This matters more for CER data than for most government data:
projects relinquish ACCUs retroactively, the CER transfers
projects between proponents, methods are reclassified (e.g.
post-Chubb-Review status changes), and the Quarterly Carbon
Market Report occasionally restates prior quarters. A snapshot
pin is the minimum evidence a reviewer needs to verify a
published carbon-market claim.
}
\examples{
cer_snapshot("2026-04-24")
cer_snapshot()
cer_snapshot(NULL)
}
\seealso{
Other reproducibility: 
\code{\link{cer_cite}()},
\code{\link{cer_deposit_zenodo}()},
\code{\link{cer_legislative_instrument}()},
\code{\link{cer_manifest}()},
\code{\link{cer_manifest_clear}()},
\code{\link{cer_manifest_write}()},
\code{\link{cer_sha256}()}
}
\concept{reproducibility}
