$success
[1] FALSE

$message
$message$message
[1] "have"        "2 arguments" "has"         "1"          

$message$wrap
$message$wrap[[1]]
NULL

$message$wrap[[2]]
NULL



$call.match
fun(1)

$call.ind
NULL

$call.ind.sub.par
NULL

$call.orig
fun(1)

$success
[1] FALSE

$message
$message$message
[1] "be"            "a call to `+`" "is"            "\"symbol\""   

$message$wrap
$message$wrap[[1]]
NULL

$message$wrap[[2]]
NULL



$call.match
a + (b + c)

$call.ind
NULL[[2]]

$call.ind.sub.par
$call.ind.sub.par[[1]]
NULL

$call.ind.sub.par[[2]]
[1] 2


$call.orig
a + (b + c)

$success
[1] FALSE

$message
$message$message
[1] "be"           "\"symbol\""   "is"           "\"language\""

$message$wrap
$message$wrap[[1]]
NULL

$message$wrap[[2]]
NULL



$call.match
(a + b) + c

$call.ind
NULL[[2]][[2]]

$call.ind.sub.par
$call.ind.sub.par[[1]]
NULL

$call.ind.sub.par[[2]]
[1] 2


$call.orig
(a + b) + c

$success
[1] FALSE

$message
$message$message
[1] "not be" "`x`"    ""       ""      

$message$wrap
$message$wrap[[1]]
NULL

$message$wrap[[2]]
NULL



$call.match
fun(x, e = x, y)

$call.ind
NULL$e

$call.ind.sub.par
$call.ind.sub.par[[1]]
NULL

$call.ind.sub.par[[2]]
e


$call.orig
fun(x, e = x, y)

$success
[1] FALSE

$message
$message$message
[1] "have"                          "argument `e` after argument 1"
[3] "has"                           "unnamed argument"             

$message$wrap
$message$wrap[[1]]
NULL

$message$wrap[[2]]
NULL



$call.match
fun(a, b, a)

$call.ind
NULL

$call.ind.sub.par
NULL

$call.orig
fun(a, b, a)

# Actually use a function (and not just name of fun)

$success
[1] FALSE

$message
$message$message
[1] "have"                             "argument `bcd` as first argument"
[3] "has"                              "`c`"                             

$message$wrap
$message$wrap[[1]]
NULL

$message$wrap[[2]]
NULL



$call.match
fun(abc = a, bcd = b, efg = fun(c = 1))

$call.ind
NULL[[4]]

$call.ind.sub.par
$call.ind.sub.par[[1]]
NULL

$call.ind.sub.par[[2]]
[1] 4


$call.orig
fun(a, b, fun(c = 1))