Internal functions to lazy load a database of R objects.
lazyLoad(filebase, envir = parent.frame(), filter)
lazyLoadDBexec(filebase, fun, filter)
The file path to the database, with no extension.
The environment into which objects are loaded.
An optional function which when called on a a character vector of object names returns a logical vector: only objects for which this is true will be loaded.
Function of one argument, an environment.
These are internal functions for use only by R itself.
The function lazyLoad
is the workhorse function called by the
package loader to load the code for a package from a database. The
database consists of two binary files, filebase.rdb
(the
objects) and filebase.rdx
(an index).
The objects are not themselves loaded into envir
: rather
promises are created that will load the object from the database on
first access. (See delayedAssign
.)
The function lazyLoadDBexec
contains the core implementation
and is also used by the mechanism for loading processed help file
data.