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.null | always returns NULL.
is.null | returns 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 6.1.5-18
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