play.RdFunction to start the chess trainer.
play(lang="en", online, ...)This is the main function to start the chess trainer. See the chesstrainer-package documentation for an introduction to the package.
On startup, the chess trainer checks for internet connectivity (which is needed to query the Lichess databases). When offline, this check can cause a slight delay on startup. To avoid this delay, you can set online=FALSE.
All of the settings of the chess trainer can be controlled from within the chess trainer (i.e., while it is running). For advanced users, the ‘...’ argument can also be used to adjust all of the settings on startup. This is undocumented behavior though, so correct usage of this argument requires understanding the internals of the package.
The function does not return an object.
Most of the interactions with the chess trainer happen in the plotting window where the board is drawn and the pieces are moved. However, for some actions, one must switch to the R console. Unfortunately, except when using R under Windows with Rgui, there is no programmatic way in R to activate the console or the plotting window. Therefore, one must manually switch to the console or back to the plotting window, which is a bit tedious. However, your operating system may allow activating windows via the command line through various means. For example, under Linux with an X Window manager (not Wayland unfortunately), this should be possible with the wmctrl command. To make use of such functionality, one can pass two strings via arguments called switch1 and switch2 to the play() function that are evaluated whenever a switch to the R console or back to the plotting window should happen. For example, with:
play(switch1="system('wmctrl -x -a gnome-terminal')",
switch2="system('wmctrl -x -a r_x11')")
one may be able to achieve this automatic window switching. Of course, this requires wmctrl to be installed and the window names must match those used by the operating system. Under macOS, it should be possible to achieve the same thing using osascript. Under Windows, the trainer uses the bringToTop() function to achieve the same thing automatically when using Rgui, so there is no need to use the switch1 and switch2 arguments.
# start playing
if (FALSE) { # \dontrun{
play()
} # }