# Symbolic objects and functions are callable:
is_callable(quote(foo))
is_callable(base::identity)
# node_poke_car() lets you modify calls without any checking:
lang <- quote(foo(10))
node_poke_car(lang, current_env())
# Use is_callable() to check an input object is safe to put as CAR:
obj <- base::identity
if (is_callable(obj)) {
lang <- node_poke_car(lang, obj)
} else {
abort("`obj` must be callable")
}
eval_bare(lang)
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