

call {base}                                  R Documentation

_F_u_n_c_t_i_o_n _C_a_l_l_s

_U_s_a_g_e_:

     call(name, ...)

     is.call(expr)
     as.call(expr)

_V_a_l_u_e_:

     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 `expr' is a
     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 oth-
     erwise terminates with an error message.

_S_e_e _A_l_s_o_:

     `do.call' for calling a function by name and argument
     list; `Recall' for recursive calling of functions;
     further `is.language', `expression', `function'.

_E_x_a_m_p_l_e_s_:

     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

