Method: Continuation#call

Defined in:

cont.c

#call(args, ...) ⇒ Object #[](args, ...) ⇒ Object

Invokes the continuation. The program continues from the end of the #callcc block. If no arguments are given, the original #callcc returns nil. If one argument is given, #callcc returns it. Otherwise, an array containing args is returned.

callcc {|cont|  cont.call }           #=> nil
callcc {|cont|  cont.call 1 }         #=> 1
callcc {|cont|  cont.call 1, 2, 3 }   #=> [1, 2, 3]

# File 'cont.c', line 1646

static VALUE
rb_cont_call(int argc, VALUE *argv, VALUE contval)
{
    rb_context_t *cont = cont_ptr(contval);
    rb_thread_t *th = GET_THREAD();

    if (cont_thread_value(cont) != th->self) {
        rb_raise(rb_eRuntimeError, "continuation called across threads");
    }
    if (cont->saved_ec.protect_tag != th->ec->protect_tag) {
        rb_raise(rb_eRuntimeError, "continuation called across stack rewinding barrier");
    }
    if (cont->saved_ec.fiber_ptr) {
        if (th->ec->fiber_ptr != cont->saved_ec.fiber_ptr) {
            rb_raise(rb_eRuntimeError, "continuation called across fiber");
        }
    }
    rollback_ensure_stack(contval, th->ec->ensure_list, cont->ensure_array);

    cont->argc = argc;
    cont->value = make_passing_arg(argc, argv);

    cont_restore_0(cont, &contval);
    UNREACHABLE_RETURN(Qnil);
}