These functions are soft-deprecated, please use is_call()
and its
n
argument instead.
is_lang(x, name = NULL, n = NULL, ns = NULL)is_unary_lang(x, name = NULL, ns = NULL)
is_binary_lang(x, name = NULL, ns = NULL)
quo_is_lang(quo)
An object to test. If a formula, the right-hand side is extracted.
An optional name that the call should match. It is
passed to sym()
before matching. This argument is vectorised
and you can supply a vector of names to match. In this case,
is_call()
returns TRUE
if at least one name matches.
An optional number of arguments that the call should match.
The namespace of the call. If NULL
, the namespace
doesn't participate in the pattern-matching. If an empty string
""
and x
is a namespaced call, is_call()
returns
FALSE
. If any other string, is_call()
checks that x
is
namespaced within ns
.
A quosure to test.