lazyload: Lazy Load a Database of R Objects

lazyLoadR Documentation

Lazy Load a Database of R Objects


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.


Luke Tierney