The rstudioapi
package provides a small family of
functions that can be used to interact with documents open in an RStudio
session. For example, the following code could be used to insert a ‘last
modified’ comment at the start of a document:
# construct the text to be inserted
fmt <- "# This document was last modified on %s.\n"
text <- sprintf(fmt, Sys.Date())
# specify a range where this text should be inserted; here,
# we use the first line; that is, the 'range' between the start
# of the first row, and the start of the second row
range <- rstudioapi::document_range(c(1, 0), c(2, 0))
rstudioapi::insertText(range, text)
By default, these APIs target the editor instance either currently
focused by the user, or when no such editor is currently focused, the
last focused editor. If you need to target a specific editor instance
(for example, you want to write code that inserts text into the
console), you can use getConsoleEditorContext()
to get the
id
for the console editor:
# get console editor id
context <- rstudioapi::getConsoleEditorContext()
id <- context$id
# send some R code to the console
rstudioapi::insertText(text = "print(1 + 1)", id = id)
# see also: `getActiveEditorContext()`, `getSourceEditorContext()`
You can also modify the cursor position through the use of the
setCursorPosition()
and setSelectionRanges()
APIs.
# put the cursor at the end of the document -- note that here,
# `Inf` is automatically truncated to the actual length of the
# document
rstudioapi::setCursorPosition(Inf)
# select the first 10 even lines in the document
ranges <- lapply(seq(2, by = 2, length.out = 10), function(start) {
rstudioapi::document_range(
c(start, 0),
c(start, Inf)
)
})
rstudioapi::setSelectionRanges(ranges)
See the ?"rstudio-documents"
help page for more
details.