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Type checks - Other types

predicates-other-types.Rd

Test if object is of a specific type (typeof()). The test is invariant to attributes such as class. The general is_type() checks for any user-supplied type.

See the Details section for the full list of types.

Functions from rlang: rlang::is_null(), rlang::is_weakref().

Usage

is_type(x, type, n = NULL)

is_null()

is_promise(x)

is_dots(x, n = NULL)

is_weakref(x)

is_bytecode(x)

is_externalptr(x)

is_char(x)

is_any(x)

Arguments

x

[any] An object to test.

type

[character(1)] A type to test for, as returned by typeof().

n

[integer(1) | NULL] Length of x, set to NULL to not test.

Value

[TRUE | FALSE] The scalar result of the test.

Details

The full list of R object types (typeof()) can be seen in "R Internals" section 1.1.3.

The existing types and their corresponding C SEXP types are:

  • Atomic vectors: "logical"/LGLSXP, "integer"/INTSXP, "double"/"numeric"/REALSXP, "complex"/CPLXSXP, "raw"/RAWSXP.

  • Lists: "list"/VECSXP, "pairlist"/LISTSXP.

  • Objects: "s4"/S4SXP, "object"/OBJSXP.

  • Language-related: "symbol"/"name"/SYMSXP, "language"/LANGSXP, "expression"/EXPRSXP.

  • Functions: "closure"/CLOSXP, "builtin"/SPECIALSXP, "special"/BUILTINSXP.

  • Promises: "promise"/PROMSXP, "..."/DOTSXP.

  • Environments: "environment"/ENVSXP.

  • Null: "NULL"/NILSXP.

  • Bytecode: "bytecode"/BCODESXP.

  • External pointer: "externalptr"/EXTPTRSXP.

  • Weak reference: "weakref"/WEAKREFSXP.

  • Internal-only: "char"/CHARSXP, "any"/ANYSXP.

Examples

is_type(1:10, "integer") #> TRUE
#> [1] TRUE
is_type(NULL, "NULL") #> TRUE
#> [1] TRUE