checkExists: Checks to see whether an object exists and, if not, executes...

In jmacdon/oligoClasses: Classes for high-throughput arrays supported by oligo and crlmm

Description

Only loads an object if the object name is not in the global environment. If not in the global environment and the file exists, the object is loaded (by default). If the file does not exist, the function FUN is run.

Usage

checkExists(.name, .path = ".", .FUN, .FUN2, .save.it=TRUE, .load.it, ...)

Arguments

.name	Character string giving name of object in global environment
.path	Path to where the object is saved.
.FUN	Function to be executed if <name> is not in the global environment and the file does not exist.
.FUN2	Not currently used.
.save.it	Logical. Whether to save the object to the directory indicaged by path. This argument is ignored if the object was loaded from file or already exists in the .GlobalEnv.
.load.it	Logical. If load.it is TRUE, we try to load the object from the indicated path. The returned object will replace the object in the .GlobalEnv unless the object is bound to a different name (symbol) when the function is executed.
...	Additional arguments passed to FUN.

Value

Could be anything – depends on what FUN, FUN2 perform.

Future versions could return a 0 or 1 indicating whether the function performed as expected.

Author(s)

R. Scharpf

Examples

path <- tempdir()
dir.create(path)
x <- 3+6
x <- checkExists("x", .path=path, .FUN=function(y, z) y+z, y=3, z=6)
rm(x)
x <- checkExists("x", .path=path, .FUN=function(y, z) y+z, y=3, z=6)
rm(x)
x <- checkExists("x", .path=path, .FUN=function(y, z) y+z, y=3, z=6)
rm(x)
##now there is a file called x.rda in tempdir().  The file will be loaded
x <- checkExists("x", .path=path, .FUN=function(y, z) y+z, y=3, z=6)
rm(x)
unlink(path, recursive=TRUE)

jmacdon/oligoClasses documentation built on Aug. 11, 2020, 12:32 a.m.