[R] MakeActiveBinding help needed
Carl Witthoft
carl at witthoft.com
Wed Jan 6 23:30:07 CET 2010
Hi,
I wanted a Q&D way to open a new graphics window but keep the focus in
the console window (under Windows and the Rgui), so I wrote a line into
my Rprofile.site file as follows:
invisible(makeActiveBinding('newdev', function(...)
dev.new(restoreConsole=T), .GlobalEnv))
(That is all on one line, incase the mailer re-parses it). This gives me
a command "newdev" which does not require me to enter a pair of
parentheses to execute it.
This worked just fine so far as the command goes. Here's the problem:
this definition is stored as part of my .Rdata file, and the next time I
start up R, I get a crash. I tracked that down to an odd fact: while
R is loading this definition from .Rdata, it tries to execute the
command, i.e. open a graphics window! Since the graphics library hasn't
been loaded yet, crash happens.
I re-wrote my definition to
invisible(makeActiveBinding('newdev', function(...) {library(graphics);
dev.new(restoreConsole=T)}, .GlobalEnv))
and then R booted up just fine, except that two new graphics windows
were created -- one from loading "newdev" from .Rdata and one from
executing the Rprofile script with the "newdev" definition in it.
So my question is: is there some way I can define this
makeActiveBinding item without R trying to execute it at the point of
loading (either from Rprofile or from .Rdata)?
thanks
Carl
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