inherits_any()
is like base::inherits()
but is more explicit
about its behaviour with multiple classes. If classes
contains
several elements and the object inherits from at least one of
them, inherits_any()
returns TRUE
.
inherits_all()
tests that an object inherits from all of the
classes in the supplied order. This is usually the best way to
test for inheritance of multiple classes.
inherits_only()
tests that the class vectors are identical. It
is a shortcut for identical(class(x), class)
.
inherits_any(x, class)
inherits_all(x, class)
inherits_only(x, class)
An object to test for inheritance.
A character vector of classes.
obj <- structure(list(), class = c("foo", "bar", "baz"))
# With the _any variant only one class must match:
inherits_any(obj, c("foobar", "bazbaz"))
#> [1] FALSE
inherits_any(obj, c("foo", "bazbaz"))
#> [1] TRUE
# With the _all variant all classes must match:
inherits_all(obj, c("foo", "bazbaz"))
#> [1] FALSE
inherits_all(obj, c("foo", "baz"))
#> [1] TRUE
# The order of classes must match as well:
inherits_all(obj, c("baz", "foo"))
#> [1] FALSE
# inherits_only() checks that the class vectors are identical:
inherits_only(obj, c("foo", "baz"))
#> [1] FALSE
inherits_only(obj, c("foo", "bar", "baz"))
#> [1] TRUE