NULL
The Null Object

Description

Coerces or tests for NULL objects.

Usage

as.null(x, ...)
as.null.default(x, ...)
is.null(x)

Arguments

x any object.
... other optional arguments to pass to or from the method. Reserved for future use.

Details

Both is.null and as.null are generic. Currently, only as.null has defined a default method.
Value
as.nullalways returns NULL.
is.nullreturns TRUE if x is NULL and returns FALSE if x is not NULL.
Warning
An object can be of length 0 and not be NULL. See the examples section.
See Also
is.na
Examples
is.null(character(0)) # returns FALSE 
as.null(list(a=1:5, b=1:10))
Package base version 6.1.1-7
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