Learn R Programming
purrr (version 0.2.1)

type-predicates: Type predicates

Description

These type predicates aim to make type testing in R more consistent. They are wrappers around typeof, so operate at a level beneath S3/S4 etc.

Usage

is_list(x)
is_atomic(x)
is_vector(x)
is_numeric(x)
is_integer(x)
is_double(x)
is_character(x)
is_logical(x)
is_null(x)
is_function(x)

Arguments

x
object to be tested.

Details

Compare to base R functions:
  • Unlikeis.atomic(),is_atomic()does not returnTRUEforNULL.
  • Unlikeis.vector(),is_vector()test if an object is an atomic vector or a list.is.vectorchecks for the presence of attributes (other than name).
  • is_numeric()is not generic so, (e.g.) dates and date times areTRUE, notFALSE.
  • is_function()returnsTRUEonly for regular functions, not special or primitive functions.

See Also

bare-type-predicates scalar-type-predicates