| call {base} | R Documentation |
Create or test for objects of mode "call".
call(name, ...) is.call(x) as.call(x)
name |
a character string naming the function to be called. |
x |
an arbitrary R object. |
call returns an unevaluated function call, that is, an
unevaluated expression which consists of the named function applied to
the given arguments (name must be a quoted string which gives
the name of a function to be called).
is.call is used to determine whether x is a call (i.e.,
of mode "call").
It is not possible to coerce objects to mode call (objects either are
calls or they are not calls). as.call returns its argument if
it is a call and otherwise terminates with an error message.
do.call for calling a function by name and argument
list;
Recall for recursive calling of functions;
further
is.language,
expression,
function.
is.call(call) #-> FALSE: Functions are NOT calls
# set up a function call to round with argument 10.5
cl <- call("round", 10.5)
is.call(cl)# TRUE
cl
# such a call can also be evaluated.
eval(cl)# [1] 10