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rlang (version 0.0.0.9000)

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, n = NULL)


is_atomic(x, n = NULL)


is_vector(x, n = NULL)


is_integer(x, n = NULL)


is_double(x, n = NULL)


is_character(x, n = NULL)


is_logical(x, n = NULL)


is_null(x)

Arguments

x
Object to be tested.
n
Expected length of a vector.

Details

Compare to base R functions:
  • The predicates for vectors include the n argument for pattern-matching on the vector length.
  • 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_function() returns TRUE only for regular functions, not special or primitive functions.

See Also

bare-type-predicates scalar-type-predicates