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rlang (version 0.2.2)

is_lang: Is object a call?

Description

These functions are soft-deprecated, please use is_call() and its n argument instead.

Usage

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)

Arguments

x

An object to test. If a formula, the right-hand side is extracted.

name

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.

n

An optional number of arguments that the call should match.

ns

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.

quo

A quosure to test.