r - How to fix 'no item called "package:pkg" on the search list' without using library(pkg)? -

i writing package named testpkg , have put quantmod in depends section of description file.

i have written following functions:

#' hello1 #' #' @return na #' @export hello1 <- function() {   print("hello1!")   quantmod::is.hlc("hello, world!") }  #' hello2 #' #' @return na #' @export hello2 <- function () {      x <- structure(c(25.85, 25.639999, 26.700001, 26.26, 26.92, 27.870001,                    25.26, 25.52, 26.66, 25.610001, 26.85, 27.74, 26352700, 32512200,                    64264600, 25.610001, 26.85, 27.74),                  .indexclass = "date", tclass = "date", .indextz = "utc", tzone = "utc",                  src = "yahoo", updated = structure(1437653990.9303, class = c("posixct",                                                                                "posixt")),                  class = c("xts", "zoo"), index = structure(c(1167782400,                                                               1167868800, 1167955200),                                                             tzone = "utc",                                                             tclass = "date"),                  .dim = c(3l, 6l), .dimnames = list(null, c("yhoo.open", "yhoo.high", "yhoo.low",                                                             "yhoo.close", "yhoo.volume", "yhoo.adjusted")))     print(x)     quantmod::chartseries(x)  } 

now, when go project , run testpkg::hello1(), output expected.

however, if run testpkg::hello2(), can see x printed plot not generated. error:

error in as.environment("package:quantmod") :    no item called "package:quantmod" on search list 

i know can fix calling library(quantmod) before making call testpkg::hello2() seems odd me testpkg::hello1() can run error-free without calling library(quantmod). reason , there alternative way run testpkg::hello2() without calling library(quantmod) first?