[Rd] recursive default argument reference in debugger (PR#2656)

[pburns at pburns.seanet.com]

Full_Name: Patrick Burns
Version: 1.6.1
OS: Linux
Submission from: (NULL) (217.35.44.203)


# the setup

 fjj.bd <-
function (x, y=x$b[, c("lower", "upper"), drop=FALSE])
{
        y
}

jjb0 <- list(b=array(1:3, c(1, 3), list("A", c("", "", "C"))))

options(error=dump.frames)

# creating the problem

> fjj.bd(jjb0)
Error in fjj.bd(jjb0) : subscript out of bounds
> debugger()
Message:  Error in fjj.bd(jjb0) : subscript out of bounds
Available environments had calls:
1: fjj.bd(jjb0)

Enter an environment number, or 0 to exit  Selection: 1
Error in get(.obj, envir = dump[[.selection]]) : 
        recursive default argument reference


The problem is that "debugger" gets an error when trying to
go into the dump.  I don't understand what is going on, but
it doesn't have to do with the actual names of the objects --
the same thing happens if all the names are changed.

This is precisely the same on Linux with 1.6.1 and Windows
with 1.6.2.