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purrr (version 0.2.2.2)

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:

  • Unlike is.atomic(), is_atomic() does not return TRUE for NULL.

  • Unlike is.vector(), is_vector() test if an object is an atomic vector or a list. is.vector checks for the presence of attributes (other than name).

  • is_numeric() is not generic so, (e.g.) dates and date times are TRUE, not FALSE.

  • is_function() returns TRUE only for regular functions, not special or primitive functions.

See Also

bare-type-predicates scalar-type-predicates