exists.not.function {NCmisc}

Does object exist ignoring functions The exists() function can tell you whether an object exists at all, or whether an object exists with a certain type, but it can be useful to know whether an object exists as genuine data (and not a function) which can be important when a variable or object is accidently or intentionally given the same name as a function. This function usually returns a logical value as to the existence of the object (ignoring functions) but can also be set to return the non-function type if the object exists.

Description

Does object exist ignoring functions

The exists() function can tell you whether an object exists at all, or whether an object exists with a certain type, but it can be useful to know whether an object exists as genuine data (and not a function) which can be important when a variable or object is accidently or intentionally given the same name as a function. This function usually returns a logical value as to the existence of the object (ignoring functions) but can also be set to return the non-function type if the object exists.

Usage

exists.not.function(x, ret.type = FALSE)

Arguments

x

the object name to search for

ret.type

logical, if TRUE then will return the objects' type (if it exists) rather than TRUE or FALSE. If the object doesn't exist the empty string will be returned as the type.

Value

logical, whether non-function object exists, or else the type if ret.type=TRUE

Author(s)

Nicholas Cooper

Examples

x <- "test"
# the standard exists function, for all modes, correct mode, and other modes:
exists("x")
exists("x",mode="character")
exists("x",mode="numeric")
# standard case for a non-function variable
exists.not.function("x",TRUE)
# compare results for a non-existent variable
exists("aVarNotSeen")
exists.not.function("aVarNotSeen")
# compare results for variable that is a function
exists("mean")
exists.not.function("mean")
# define a variable with same name as a function
mean <- 1.4
# exists.not.function returns the type of the variable ignoring the function of the same name
exists.not.function("mean",TRUE)
exists("mean",mode="function")
exists("mean",mode="numeric")