# NOT RUN {
## DDE exchange protocol is available ONLY under Windows!
## Also, this cannot be run by examples() but should be OK when pasted
## into an interactive R session with the tcltk package loaded
## Here is how you can test these features under Windows
options(use.DDE = TRUE)
library(svIDE) # This should automatically start the
## DDE server named 'TclEval SciViewsR', according to the option set
## Get some data in the user workspace
data(trees)
a <- 1
b <- "some text in the first instance of R"
#######################################################
## To test these functions in an external program, we need now
## to start a second instance of R. In this second instance, enter:
library(tcltk)
.Tcl("package require dde")
.Tcl("dde services TclEval {}")
## You should get 'TclEval SciViewsR' in the list
## if the server in the first instance is running
## Now, request a calltip for the function 'ls'
## This is done in two steps:
## 1) Execute the command 'guiCallTip' with this code chunk as argument
.Tcl("dde execute TclEval SciViewsR {guiCallTip {res <- ls(}}")
## 2) Retrieve the calltip from the variable SciViewsR_CallTip
.Tcl("dde request TclEval SciViewsR SciViewsR_CallTip")
## Another way to trigger DDE commands (for programs that do not support
## DDE is to use 'execdde.exe' of the tcltk2 package (see ?tk2dde)
## It is also possible to copy the calltip to a file, or to the clipboard
## by specifying it after the command (also the two additional arguments
## have their default values changed)
.Tcl("dde execute TclEval SciViewsR {guiCallTip {library(} clipboard TRUE 40 TRUE}")
## Look at what is in the clipboard
cat(readClipboard(), "\n")
## The process is similar to get completion lists
.Tcl("dde execute TclEval SciViewsR {guiComplete {iris$}}")
.Tcl("dde request TclEval SciViewsR SciViewsR_Complete")
## Get the list of variables in the user workspace of the first R instance
## into the clipboard (use also the other arguments to get the type of objects)
.Tcl("dde execute TclEval SciViewsR {guiComplete {} clipboard TRUE { - }}")
## Look at what is in the clipboard
cat(readClipboard(), "\n")
# }
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