If a code chunk has turned on the chunk option cache = TRUE, a cache
database will be established after the document is compiled. You can use this
function to manually load the database anywhere in the document (even before
the code chunk). This makes it possible to use objects created later in the
document earlier, e.g. in an inline R expression before the cached code
chunk, which is normally not possible because knitr compiles the
document in a linear fashion, and objects created later cannot be used before
they are created.
load_cache(
label,
object,
notfound = "NOT AVAILABLE",
path = opts_chunk$get("cache.path"),
dir = opts_knit$get("output.dir"),
envir = NULL,
lazy = TRUE
)Invisible NULL when object is not specified (the cache
database will be loaded as a side effect), otherwise the value of the
object if found.
The chunk label of the code chunk that has a cache database.
The name of the object to be fetched from the database. If it
is missing, NULL is returned).
A value to use when the object cannot be found.
Path of the cache database (normally set in the global chunk
option cache.path).
Path to use as the working directory. Defaults to the output
directory if run inside a knitr context and to the current working
directory otherwise. Any relative path is defined from dir.
Environment to use for cache loading, into which all objects in
the cache for the specified chunk (not just that in object) will be
loaded. Defaults to the value in knit_global.
Whether to lazyLoad the cache database (depending
on the chunk option cache.lazy = TRUE or FALSE of that code
chunk).
See the example #114 at https://github.com/yihui/knitr-examples.